Consumer Information Regulations Uniform Tire Quality Grading Standards

DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 575

[Docket No. 94-30, Notice 2]

RIN 2127-AF17

Consumer Information Regulations Uniform Tire Quality Grading

Standards

AGENCY: National Highway Traffic Safety Administration (NHTSA),

Department of Transportation (DOT).

ACTION: Notice of proposed rulemaking.

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SUMMARY: This notice proposes to amend the Uniform Tire Quality Grading

Standards to:

1. Revise treadwear testing procedures to maintain the base course

wear rate of course monitoring tires at its current value. That

revision should eliminate treadwear grade inflation, reduce testing

expenses, and reduce the adverse environmental consequences of

operating testing convoys;

2. Create a new traction grading category of ``AA'' in addition to

the current traction grades of A, B, and C to differentiate those tires

with the highest traction characteristics from lower performing tires;

3. Replace the temperature resistance grade with a rolling

resistance/fuel economy grade. This change would provide a measure of a

key fuel economy characteristic of tires, and responds to the

President's Climate Change Action Plan.

DATES: Comments on this notice must be received on or before July 10,

1995.

ADDRESSES: Comments should refer to the docket and notice number shown

above and be submitted to Docket Section, National Highway Traffic

Safety Administration, 400 Seventh Street, SW, Room 5111, Washington,

DC 20590. Docket room hours are from 9:30 a.m. to 4 p.m., Monday

through Friday.

FOR FURTHER INFORMATION CONTACT: Mr. Orron Kee, Office of Market

Incentives, Office of the Associate Administrator for Rulemaking,

National Highway Traffic Safety Administration, 400 Seventh Street,

SW., Room 5320, Washington, DC 20590, telephone (202) 366-0846.

SUPPLEMENTARY INFORMATION:

Table of Contents

on,

DC 20590. Docket room hours are from 9:30 a.m. to 4 p.m., Monday

through Friday.

FOR FURTHER INFORMATION CONTACT: Mr. Orron Kee, Office of Market

Incentives, Office of the Associate Administrator for Rulemaking,

National Highway Traffic Safety Administration, 400 Seventh Street,

SW., Room 5320, Washington, DC 20590, telephone (202) 366-0846.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Background

II. April 25, 1994 Request for Comments

A. Treadwear

1. Treadwear Test and Calculation Procedures

a. Candidate Tires

b. Course Monitoring Tires

2. Treadwear Grade Inflation

3. Possible Solutions to Treadwear Grade Inflation

B. Traction

1. Traction Test and Calculation Procedures

2. Ability of Traction Grading System to Differentiate Highest

Traction Tires

3. Possible Solutions to Traction Grading Problems

C. Temperature and Rolling Resistance/Fuel Economy

1. Temperature Resistance

2. Rolling Resistance/Fuel Economy

3. Issues Regarding Temperature/Rolling Resistance/Fuel Economy

III. Summary of Public Comments, Agency Decisions, Benefits and

Costs

A. Treadwear

1. Summary of Comments

2. Agency Decision

3. Costs and Benefits

B. Traction

1. Public Comments

2. Agency Decision

3. Costs and Benefits

C. Temperature/Rolling Resistance/Fuel Economy

1. Public Comments

2. Agency Decision

a. Temperature Resistance

b. Rolling Resistance/Fuel Economy

3. Costs and Benefits

D. Leadtime

IV. Rulemaking Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and

Procedures

B. Regulatory Flexibility Act

C. National Environmental Policy Act

D. Federalism

E. Civil Justice Reform

V. Comments

I. Background

stance/Fuel Economy

1. Public Comments

2. Agency Decision

a. Temperature Resistance

b. Rolling Resistance/Fuel Economy

3. Costs and Benefits

D. Leadtime

IV. Rulemaking Analyses and Notices

A. Executive Order 12866 and DOT Regulatory Policies and

Procedures

B. Regulatory Flexibility Act

C. National Environmental Policy Act

D. Federalism

E. Civil Justice Reform

V. Comments

I. Background

49 U.S.C. 30123(e) requires the Secretary of Transportation to

prescribe a uniform system for grading motor vehicle tires to assist

consumers in making informed choices when purchasing

tires. NHTSA implemented this congressional mandate by issuing the

Uniform Tire Quality Grading Standards (UTQGS) (49 CFR Sec. 575.104).

The UTQGS are applicable to most passenger car tires.

The UTQGS require manufacturers to grade their tires for treadwear,

traction, and temperature resistance. Those characteristics were

adopted by NHTSA after an extended process of study, testing, and

public comment. NHTSA believed that those three characteristics

provided the best balance of tire properties that would be the most

meaningful to consumers. Because those three characteristics interact

with each other, however, manufacturers must use care in trying to

improve any particular characteristic since improving one

characteristic could detract from one or both of the other

characteristics. For example, treadwear life could be extended by

adjusting the tire compounds to produce a harder tread. That

adjustment, however, could detract from traction performance. Tread

life could also be extended by adding more rubber compound to the

tread. That addition, however, could increase rolling resistance,

causing greater internal heating. The increased heating could, in turn,

result in temperature buildup and possibly result in tire failure.

II. April 25, 1994 Request for Comments

der tread. That

adjustment, however, could detract from traction performance. Tread

life could also be extended by adding more rubber compound to the

tread. That addition, however, could increase rolling resistance,

causing greater internal heating. The increased heating could, in turn,

result in temperature buildup and possibly result in tire failure.

II. April 25, 1994 Request for Comments

On April 25, 1994, NHTSA published a Request for Comments in the

Federal Register (59 FR 19686) requesting public comment on possible

improvements to the UTQGS. Specifically, the agency requested comments

on ways to cure a problem of treadwear grade inflation, whether to add

an additional rating category to provide a means of differentiating

tires with the highest traction characteristics, and whether to

commence the grading of tires for rolling resistance. In view of the

complexity of the subject matter of this notice, the agency is

repeating much of the background explanatory discussion in the Request

for Comments.

A. Treadwear

In the Request for Comments, the agency described the testing of

candidate tires, the role played by course monitoring tires in

adjusting the measured wear of candidate tires and the possible sources

of treadwear rating inflation.

1. Treadwear Test and Calculation Procedures

a. Candidate tires. The treadwear grade is considered the most

meaningful of the three grades to the public, but treadwear is also the

most difficult of the three characteristics to grade.

The procedures which NHTSA follows for testing tires for compliance

with the UTQGS are specified in 49 CFR 575.104(e), Treadwear grading

conditions and procedures. NHTSA tests treadwear by running the tires

being tested, called candidate tires, on test vehicles multiple times

over a 400-mile test course on public roads in the vicinity of San

Angelo, Texas

the three characteristics to grade.

The procedures which NHTSA follows for testing tires for compliance

with the UTQGS are specified in 49 CFR 575.104(e), Treadwear grading

conditions and procedures. NHTSA tests treadwear by running the tires

being tested, called candidate tires, on test vehicles multiple times

over a 400-mile test course on public roads in the vicinity of San

Angelo, Texas. The test vehicles travel in convoys of two or four

passenger cars, light trucks, or multipurpose passenger vehicles, each

with a GVWR of 10,000 pounds or less. To equalize operating conditions,

the drivers are changed at regular intervals, the tires are rotated to

different positions on the vehicles, and the vehicles are rotated to

different positions within the convoy.

Candidate tires are subjected to a 6,400 mile test. At the end of

the test, the total measured wear is multiplied by a factor that

reflects the severity of the environmental conditions during the test

(the purpose and derivation of that factor is explained below in the

discussion of course monitoring tires). The result of the

multiplication is the adjusted wear rate (AWR) of the candidate tires.

The AWR is extrapolated to wearout, which is considered to be the point

at which \1/16\th of an inch of tread remains. The extrapolated figure

becomes the treadwear grade. A grade of 100 indicates that the tire can

be expected to achieve 30,000 miles to wear out, as measured on the San

Angelo course. A treadwear grade of 150 should achieve 50 percent more

mileage than the one graded 100, if tested on the same course and under

the same conditions. NHTSA emphasizes, however, that the treadwear

grades are not meant to be indicative of the actual mileage every

consumer can expect from a given tire. The grades are intended to be

indicators of relative performance rather than absolute performance.

Thus, a tire graded at 150 should achieve 50 percent more mileage than

one graded at 100

ested on the same course and under

the same conditions. NHTSA emphasizes, however, that the treadwear

grades are not meant to be indicative of the actual mileage every

consumer can expect from a given tire. The grades are intended to be

indicators of relative performance rather than absolute performance.

Thus, a tire graded at 150 should achieve 50 percent more mileage than

one graded at 100. The actual tire mileage achieved by a motorist

depends on many variables, such as geographic location, road

conditions, individual driving habits, climate, weather, tire

maintenance, and so forth.

b. Course Monitoring Tires. Environmental factors like changes in

road and climatic conditions can cause course wear rates for the same

tire to vary on a daily basis. In order to compensate for the effect of

such variables on the amount of wear during a particular treadwear

convoy test, candidate tires are tested along with control tires called

course monitoring tires (CMT). Four CMT's are placed on one test

vehicle and four candidate tires with identical size designations are

placed on each other test vehicle in the convoy. CMTs are built to the

specifications of American Society for Testing and Materials (ASTM)

standard E1136, which specifies tight controls over the production,

handling, and storage of those standardized control tires.

Since CMT lots are not precisely identical, even though

manufactured to ASTM standards, a base course wear rate (BCWR) is

established for each new batch or lot of CMTs procured by the agency.

The BCWR is the calculated wear rate of that lot of CMTs under

``average'' conditions and is applied to the CMTs to adjust for the

variability in the wear rates between CMT lots. The BCWR for the new

lot is determined by running tires selected from that lot over the test

course in a convoy along with CMTs from the previous lot. The previous

CMTs are run in an attempt to determine whether and to what extent

there have been changes in the condition of the course

age'' conditions and is applied to the CMTs to adjust for the

variability in the wear rates between CMT lots. The BCWR for the new

lot is determined by running tires selected from that lot over the test

course in a convoy along with CMTs from the previous lot. The previous

CMTs are run in an attempt to determine whether and to what extent

there have been changes in the condition of the course. The measure of

those changes is called a course severity adjustment factor (CSAF). The

CSAF is determined by dividing the BCWR for the CMTs by the average

wear rate of the 4 CMTs in the test convoy. It is assumed that any

difference between the BCWR and the wear rate reflects changes in the

course. The measured wear rate of the new CMTs is then multiplied by

the CSAF to obtain the adjusted wear rate (AWR) of the new CMTs, which

then becomes the BCWR for new CMTs. This procedure is intended to make

the BCWR of new CMTs comparable to that of the previous CMTs by

removing changes in the course as a source of difference between the

BCWR of the previous CMTs and that of the new CMTs.

Upon completion of the 6,400-mile test of the candidate tires, the

BCWR of the new CMT lot is divided by the average measured wear rate of

the new CMTs in the test convoy to determine the CSAF for that convoy.

That CSAF is then applied to the wear rates of the candidate tires. The

AWR of the candidate tires is extrapolated to the point of wear out,

which then becomes the treadwear rating of the candidate

tires.

2. Treadwear Grade Inflation

NHTSA has noted significant increases in treadwear ratings since

the UTQGS became fully effective in 1980. Early in the UTQGS program,

the treadwear ratings remained at roughly the same level. As the years

progressed, however, treadwear ratings have drifted steadily upward in

both manufacturers' and NHTSA's testing results. In part, this increase

reflects the fact that current tires are of higher quality, perform

better and last longer than tires produced even a few years ago

ly effective in 1980. Early in the UTQGS program,

the treadwear ratings remained at roughly the same level. As the years

progressed, however, treadwear ratings have drifted steadily upward in

both manufacturers' and NHTSA's testing results. In part, this increase

reflects the fact that current tires are of higher quality, perform

better and last longer than tires produced even a few years ago. Such

improvements result from industry developments such as improvements in

rubber compounds, cord materials, tire designs, and tread

configurations.

The agency believes, however, that some of the increase in

treadwear grades cannot be explained by improvements in tires. A

significant amount of the unexplained increase is traceable to a

decline in the BCWRs of each successive lot of CMTs. Under the formula

for calculating treadwear, the BCWRs for CMTs and treadwear vary

inversely, Thus, as the BCWRs decrease, treadwear increases.

3. Decline in Base Course Wear Rate

Since the first lot of CMTs was procured in 1975, there has been a

steady and consistent decline in the BCWRs of each successive lot of

CMTs. Although measured wear rates for CMTs have varied, BCWRs have

steadily declined from 4.44 mils per thousand miles for the original

lot of CMTs to 1.47 mils per thousand miles for the last lot purchased

in 1993, as shown in Table 1, below:

Table 1.--CMT Wear Rates and Base Course Wear Rate Adjustment Factors

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Wear rate

(mils per

Year tested Manufacturer Series 1,000 BCWR

miles)

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1975........................ Goodyear................... Batch 1.................... 4.44 4.44

1979........................ Goodyear................... Batch 1.................... 4.08

1979........................ Goodyear................... Batch 2...................

00 BCWR

miles)

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1975........................ Goodyear................... Batch 1.................... 4.44 4.44

1979........................ Goodyear................... Batch 1.................... 4.08

1979........................ Goodyear................... Batch 2.................... 3.82 4.16

1980........................ Goodyear................... Batch 2.................... 5.29

1980........................ Goodyear................... Batch 3.................... 4.76 3.74

1984........................ Goodyear................... Batch 3.................... 4.22

1984........................ Uniroyal................... 40000...................... 3.27 2.89

1987........................ Uniroyal................... 40000...................... 5.96

1987........................ Uniroyal................... 71000...................... 4.56 2.21

1989........................ Uniroyal................... 71000...................... 5.01

1989........................ Uniroyal................... 91000...................... 4.84 2.14

1991........................ Uniroyal................... 91000...................... 6.24

1991........................ ASTM E1136................. 010000..................... 4.94 1.70

1991........................ ASTM E1136................. 010000..................... 6.96

1992........................ ASTM E1136................. 110000..................... 6.65 1.62

1992........................ ASTM E1136................. 110000..................... 5.83

1992........................ ASTM E1136................. 210000..................... 5.60 1.56

1993........................ ASTM E1136................. 210000..................... 7.21

1993........................ ASTM E1136................. 310000..................... 6.80 1.47

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ns. Further, environmental conditions, such as extremes of

temperature can directly affect the tires. The combined effect of the

environmental conditions and the emission of gases can cause changes in

the rubber compounds over time. Such changes adversely affect the

resiliency of the rubber, increasing wear rates and giving a false

indication that the test course could be becoming more severe.

To minimize the aging factor, the agency has in recent years

procured CMTs in small lots so as to reduce the interval between

determining the BCWR for a given lot and subsequently using tires from

that lot in determining the BCWR for the next lot. The agency has also

begun to store the CMTs in polyethylene bags in a warehouse in which

the temperature, although not controlled to the extent specified in

ASTM E1136, normally ranges between 60 deg. and 90 deg.. The agency

hopes that by storing the CMTs in the bags they will not be exposed to

the atmosphere, thereby diminishing the gas emissions described above

and lessening the outgas effect on the tires.

With respect to the formula for calculating BCWR, the agency

requested comment on whether the practice of recalculating the BCWR of

each new lot of CMTs should be abandoned and the wear rates of

candidate tires compared directly with those of the CMTs, that is,

without adjusting the wear rate of the new CMTs to reflect differences

(theoretically due to aging) between the wear rates of the new CMTs and

the CMTs from the previous lot. The intent of the BCWR is to provide a

common baseline by which to grade candidate tires. However, NHTSA's

practice of relating all new CMTs to the original CMTs in the manner

specified in the UTQGS has somehow distorted the treadwear grading

procedure to bring about the inflated results now being experienced

to aging) between the wear rates of the new CMTs and

the CMTs from the previous lot. The intent of the BCWR is to provide a

common baseline by which to grade candidate tires. However, NHTSA's

practice of relating all new CMTs to the original CMTs in the manner

specified in the UTQGS has somehow distorted the treadwear grading

procedure to bring about the inflated results now being experienced.

In asking whether the agency should switch to direct comparison,

the agency sought available data on whether such direct comparison of

the wear rates of CMTs and candidate tires would avoid the effects of

flaws in the current treadwear procedures. The switch to direct

comparison could result in lower, and perhaps more realistic, treadwear

ratings. On the other hand, it could change the original intent of the

CMT, which was to provide a common baseline for comparison of wear

rates, regardless of when a candidate tire was tested. In addition, it

could present a problem for the tires already graded and still in

production by having to re-test and re-grade them.

The agency posed four other questions in the notice, i.e., whether

the current ratings are misleading, whether a new system should be

developed for treadwear grading, whether the test should be changed,

and whether the BCWR computation procedure should be changed.

B. Traction

1. Traction Test and Calculation Procedures

Traction grades are established by sliding tires over test pads

also located near San Angelo, Texas. One pad consists of a wet asphalt

surface; the other, a wet concrete surface. A test trailer is equipped

with two control tires manufactured in accordance with ASTM standard

E501. The control tires are inflated to 24 pounds per square inch

(psi), statically balanced, allowed to cool to ambient temperature with

inflation pressure maintained at 24 psi, then installed on the test

trailer. Each tire is loaded to 1,085 pounds. The trailer is first

towed over the wet asphalt surface at a speed of 40 miles per hour

(mph)

es manufactured in accordance with ASTM standard

E501. The control tires are inflated to 24 pounds per square inch

(psi), statically balanced, allowed to cool to ambient temperature with

inflation pressure maintained at 24 psi, then installed on the test

trailer. Each tire is loaded to 1,085 pounds. The trailer is first

towed over the wet asphalt surface at a speed of 40 miles per hour

(mph). As one of the wheels with a control tire passes across the

asphalt, it is locked. The traction coefficient of the locked wheel is

recorded for a period of 0.5 to 1.5 seconds after lockup. The same

procedure is then followed for the same wheel/control tire as the

trailer is towed across the wet concrete surface. These tests are

conducted 10 times on each surface for that wheel/control tire. The

same tests are then conducted for the other wheel/control tire. The 20

measurements taken on each surface are averaged to find the control

tire traction coefficient for that surface. After the testing of the

control tires, those coefficients are used in calculating the traction

coefficients of the candidate tires.

In testing the candidate tires, two tires of the same type,

construction, manufacturer, line, and size designation are prepared and

tested utilizing the same procedures described above for the control

tires. The loads on the candidate tires, however, are maintained at 85

percent of the test loads specified in Sec. 575.104(h). The adjusted

traction coefficients of the candidate tires are determined in

accordance with Sec. 575.104(f)(2)(ix) and (x).

The grades of the candidate tires are designated as ``A'', ``B'',

or ``C.'' A tire that achieves both a high level of traction

performance on asphalt (above 0.47) and a high level on

concrete (above 0.35) is graded ``A.'' A tire achieving medium

traction performance (0.38 on wet asphalt and 0.26 on

wet concrete) is graded ``B.'' A tire achieving traction performance

lower than 0.38 on asphalt and 0.26 on concrete is

graded ``C.''

2

gnated as ``A'', ``B'',

or ``C.'' A tire that achieves both a high level of traction

performance on asphalt (above 0.47) and a high level on

concrete (above 0.35) is graded ``A.'' A tire achieving medium

traction performance (0.38 on wet asphalt and 0.26 on

wet concrete) is graded ``B.'' A tire achieving traction performance

lower than 0.38 on asphalt and 0.26 on concrete is

graded ``C.''

2. Ability of Traction Grading System to Differentiate Highest Traction

Tires

NHTSA's analysis of traction test data since 1989 indicates that

tire traction performance has improved to the extent that the current

grading system does not adequately differentiate between tires with

different levels of performance, particularly the highest performing

tires.

Another issue being examined by NHTSA is the implication of the

increasing number of vehicles with antilock braking systems (ABS) for

the way in which traction is measured. For non-ABS vehicles, sliding

traction is the primary traction force in panic braking since the

vehicles' wheels are locked during such braking. However, for ABS

vehicles, peak tire traction is the primary traction force since the

ABS keeps the tire rolling during panic braking.

3. Possible Solutions to Traction Grading Problems

The agency solicited comments on whether the traction ratings

should be revised to differentiate the highest performing tires. One

alternative for addressing this problem would be to adjust each grade

category so that it would represent a higher band or range of

performance than it currently does. For example, the A grade could be

adjusted so that it includes tires with traction coefficients above

0.54 on asphalt and above 0.41 on concrete, while a B

rating could include tires with traction coefficients above

0.48 and 0.35 respectively, and a C rating could

include tires with performance below that

o that it would represent a higher band or range of

performance than it currently does. For example, the A grade could be

adjusted so that it includes tires with traction coefficients above

0.54 on asphalt and above 0.41 on concrete, while a B

rating could include tires with traction coefficients above

0.48 and 0.35 respectively, and a C rating could

include tires with performance below that. Another alternative would be

to make no adjustment in the level of performance represented by the

existing grades, but create a new grade category of ``AA'' for the

highest performing tires, i.e., those tires achieving traction

coefficients above 0.54 and 0.41 respectively.

NHTSA also sought comments on whether to replace or supplement

traction grading based on sliding traction with traction grading based

on peak tire traction and asked about the cost of measuring peak

traction.

C. Temperature and Rolling Resistance/Fuel Economy

1. Temperature Resistance

The current provisions of the UTQGS require grading tires in a

third category, temperature resistance. The temperature resistance

grade indicates the extent to which heat is generated and/or dissipated

by a tire by measuring the ability of the tire to operate at high

speeds without tire failure. Heat is generated by the energy absorbed

by the tire from the friction caused by the flexing and slipping of the

rubber as it rolls along the road. That energy is wasted and appears in

the tire as heat. The more energy that is wasted, the greater the heat

buildup. If the tire is unable to dissipate that heat effectively or if

the tire is unable to resist the heat buildup, its ability to run at

high speeds without failure is reduced. Therefore, its temperature

resistance grade is lower.

Heat buildup is generally caused by some combination of tire

overloading, high speed operation, and/or improper inflation pressure,

all of which contribute to greater flexing and increased heat buildup

e that heat effectively or if

the tire is unable to resist the heat buildup, its ability to run at

high speeds without failure is reduced. Therefore, its temperature

resistance grade is lower.

Heat buildup is generally caused by some combination of tire

overloading, high speed operation, and/or improper inflation pressure,

all of which contribute to greater flexing and increased heat buildup.

Sustained high temperature can cause structural degeneration of the

tire compounds resulting in reduced tire life or outright tire failure.

NHTSA tests tires for temperature resistance utilizing the same

laboratory test wheel as the high speed performance test of Federal

motor vehicle safety standard (Standard) No. 109, New pneumatic tires.

That test is conducted at speeds up to 85 mph, while the UTQGS

temperature resistance test is run at speeds of up to 115 mph. A tire

is graded ``A'' if it completes the test at a sustained speed of 115

mph without visual evidence of tread, sidewall, ply, cord, innerliner,

or bead separation, chunking, broken cords, cracking or open splices,

and the inflation pressure is not less than the specified test

pressure. A tire is graded ``B'' if it completes the test at speeds

between 100 and 115 mph without the damage mentioned above, and is

graded ``C'' if it has successfully completed the test at speeds

between 85 and 100 mph.

2. Rolling Resistance/Fuel Economy

NHTSA considers temperature resistance to be a valid safety concern

and is unaware of any problems with the accuracy of the

ratings. However, despite the agency's efforts over the years to

educate the public by means of consumer information bulletins, press

releases, and labels affixed to tires explaining the meaning and

significance of the UTQGS ratings, NHTSA has found that most of the

tire-buying public is not aware of and/or does not understand the

significance of the temperature resistance rating

racy of the

ratings. However, despite the agency's efforts over the years to

educate the public by means of consumer information bulletins, press

releases, and labels affixed to tires explaining the meaning and

significance of the UTQGS ratings, NHTSA has found that most of the

tire-buying public is not aware of and/or does not understand the

significance of the temperature resistance rating.

Conversely, increasing interest has been shown in adding a rating

for rolling resistance on the basis that such a rating could be readily

understood by the public. The possibility of adding such a rating was

discussed at the White House Conference on Global Climate Change on

June 10 and 11, 1993 (hereinafter referred to as the Conference). At a

meeting of the Auto and Light Truck Workshop of the Transportation

Working Group of the Conference, Michelin presented a paper asserting

that the average rolling resistance for original equipment all-season

radial tires was 22.6 percent less than that for typical replacement

tires. Further, it was suggested that a 4 percent improvement in fuel

economy could be realized if replacement tires had the same rolling

resistance as original equipment tires.

As a result of the Conference, the Administration issued a report

on October 19, 1993, entitled The Climate Change Action Plan (Plan),

setting forth a series of initiatives to reduce greenhouse gas

emissions. The Plan calls for reduction of U.S. greenhouse gas

emissions to 1990 levels by the year 2000. One of the initiatives to

accomplish that goal calls for DOT, through NHTSA, to issue new rules

and test procedures requiring manufacturers to test and label tires

relative to their rolling resistance.

NHTSA expressed its belief in the Request for Comments that there

is a close relationship between temperature resistance and rolling

resistance. One of the causes of heat generation in tires, the action

of the tread on the road surface, also causes rolling resistance

, to issue new rules

and test procedures requiring manufacturers to test and label tires

relative to their rolling resistance.

NHTSA expressed its belief in the Request for Comments that there

is a close relationship between temperature resistance and rolling

resistance. One of the causes of heat generation in tires, the action

of the tread on the road surface, also causes rolling resistance. In

fact, it is the friction resulting from rolling resistance that is the

immediate cause of heat generation in the tire. Properties of the road

and of tire materials, such as roughness, softness, as well as amount

of flexing, determine the amount of friction and therefore the amount

of heat generated.

Rolling resistance is measured in a procedure similar to that used

for measuring temperature resistance, namely by running a tire under

load on a test wheel. The energy consumed in driving the tire is

measured and the energy recovered from the tire is measured by the test

equipment. The difference is the heat energy lost which is the measure

of the rolling resistance.

Safety benefits should not be lost by substituting rolling

resistance for temperature resistance since the two are related and

determined by similar tests. Standard No. 109 would continue to ensure

that all tires are capable of safe operation at speeds of up to 85 mph,

which establishes a minimum safety threshold. Further, given that the

public is not very responsive to temperature resistance ratings, the

elimination of those ratings should not cause the tire manufacturers to

lower the temperature resistance performance of their tires.

3. Issues Regarding Temperature/Rolling Resistance/Fuel Economy

The agency invited comments on a wide variety of issues relating to

temperature resistance

ety threshold. Further, given that the

public is not very responsive to temperature resistance ratings, the

elimination of those ratings should not cause the tire manufacturers to

lower the temperature resistance performance of their tires.

3. Issues Regarding Temperature/Rolling Resistance/Fuel Economy

The agency invited comments on a wide variety of issues relating to

temperature resistance. Among them were whether the rolling resistance

can be improved without detracting from the other rated tire

performance characteristics, whether the temperature resistance rating

should be supplemented by or replaced by a rolling resistance rating,

whether such a substitution would have any safety consequences, and how

rolling resistance values should be translated into improvements in

``real world'' fuel economy.

III. Summary of Public Comments, Agency Decisions and Benefits and

Costs

To preserve the continuity of discussion about each type of UTQGS

rating, the agency presents below, as one unit, the summary of public

comments, the agency decision in response to those comments, and the

costs and benefits of the decision first with respect to the treadwear

rating procedures, then traction, and then temperature/rolling

resistance.

A. Treadwear

1. Summary of Comments

Bridgestone/Firestone, Inc. (BF), The Goodyear Tire and Rubber

Company (Goodyear), General Tire (GT), Michelin, MTS Systems

Corporation (MTS), Dunlop Tire Corporation (Dunlop), Cooper Tire and

Rubber Company (Cooper), and the European Tyre and Rim Technical

Organisation (ETRTO) responded to the agency's treadwear issues. BF,

GT, and Dunlop did not consider the UTQGS treadwear grade misleading to

consumers, so long as the grade is used only to compare tires and not

project expected mileage to wearout. Goodyear, ETRTO, and Michelin, on

the other hand, believed that the treadwear rating is misleading to the

public because the treadwear test produces inconsistent results

esponded to the agency's treadwear issues. BF,

GT, and Dunlop did not consider the UTQGS treadwear grade misleading to

consumers, so long as the grade is used only to compare tires and not

project expected mileage to wearout. Goodyear, ETRTO, and Michelin, on

the other hand, believed that the treadwear rating is misleading to the

public because the treadwear test produces inconsistent results. They

argued that the inconsistencies arose from such factors as the steady

decline in the BCWR, the relatively short duration of the treadwear

test, and the low wear rates of the tires, which cause the treadwear

test to overestimate tire life. Michelin further commented that

although tire technology has improved considerably in the past few

years, treadwear grades have increased faster than technological

improvements. Michelin commented that the test course is not

sufficiently demanding.

BF, Goodyear, Cooper, and Dunlop commented that the treadwear grade

should be deleted altogether, arguing that it is not needed and is not

cost effective. Goodyear stated that manufacturers' tire warranties are

better and more meaningful to consumers, and BF asserted that NHTSA's

own figures indicate that 70 percent of the tire-buying public pay no

attention to the treadwear grade. Cooper and Dunlop asserted that the

treadwear grade is environmentally unfriendly, Dunlop contending that

every test convoy adds 22 tons of greenhouse gases to the environment

and costs $27,524.64.

Goodyear, Dunlop, Michelin, BF, and MTS commented that if the

treadwear grade remains a part of the UTQGS, a new system should be

developed for rating it. They contended that the present rating system

is too expensive, unreliable, and has too many variables. Goodyear,

Dunlop, and MTS urged development of a standard, repeatable laboratory

test, and BF, Cooper and Dunlop recommended that NHTSA participate with

the ASTM F9 Committee to develop a new indoor, environmentally friendly

test procedure

S, a new system should be

developed for rating it. They contended that the present rating system

is too expensive, unreliable, and has too many variables. Goodyear,

Dunlop, and MTS urged development of a standard, repeatable laboratory

test, and BF, Cooper and Dunlop recommended that NHTSA participate with

the ASTM F9 Committee to develop a new indoor, environmentally friendly

test procedure. This refers to a committee of the ASTM, designated the

``F9 Committee,'' which was formed to develop a laboratory test to

assess treadwear potential.

Goodyear, Michelin, BF, and MTS all agreed that the test procedure

should be changed, contending that the vehicle to vehicle rotation of

the candidate tires creates new variables in addition to the existing

ones. Finally, Goodyear, Cooper, Dunlop, BF, and GT recommended that

the BCWR be fixed at its present figure of 1.47 to achieve more

consistent results and save testing costs.

2. Agency Decision

The agency is not persuaded by the commenters' assertions that the

treadwear ratings of tires under the UTQGS are inconsistent and mislead

the public. The agency does not agree that the treadwear test results

are inconsistent. The treadwear grade provides a basis

on which to compare the relative treadwear of tires tested under

controlled conditions. The agency believes that a road test has the

inherent advantage of measuring treadwear rates under actual road

conditions. Further, the computations used in calculating the BCWR,

CSAF, and the AWR are specifically intended to make the treadwear test

results as consistent as possible.

NHTSA does not agree with commenters that suggested that the

practice of vehicle to vehicle rotation of candidate tires creates new

variables and should be changed. On the contrary. NHTSA has found, and

so stated in a previous notice (55 FR 47765) that rotation of the tires

throughout the test convoy significantly reduced the variability of

treadwear grades resulting from test car and driver factors

oes not agree with commenters that suggested that the

practice of vehicle to vehicle rotation of candidate tires creates new

variables and should be changed. On the contrary. NHTSA has found, and

so stated in a previous notice (55 FR 47765) that rotation of the tires

throughout the test convoy significantly reduced the variability of

treadwear grades resulting from test car and driver factors.

NHTSA believes that the treadwear ratings provide consumers with

reliable information on which to distinguish between the relative

performance of the different tire types and brands. They are not

intended to project the actual expected mileage of a tire. Tire

purchasers are specifically advised of this on the label required by 49

CFR 575.104(d)(1)(B)(2), which states that the treadwear rating is a

``comparative rating'' and explains what the rating represents. The

voluntary treadwear warranties provided by manufacturers do, by

contrast, indicate the amount of mileage that can be expected from a

given tire. NHTSA considers the UTQGS treadwear ratings and the

manufacturers' warranties to be complementary and, in many instances,

confirm each other. NHTSA's surveys show that 74 percent of the public

had heard of the treadwear ratings and 29 percent consider such ratings

in making their tire purchases. While 29 percent may seem a

comparatively small percentage of the tire buying public, it is large

enough to be influential. Tire manufacturers continue to make

improvements in treadwear. Further, treadwear related information is

given prominent treatment in tire advertising.

Cooper and Dunlop commented that the treadwear rating should be

deleted because the testing is expensive and ``environmentally

unfriendly.'' Since treadwear is the central feature of the

statutorily-mandated UTQGS, NHTSA is not proposing to delete treadwear.

NHTSA is well aware of the expense of treadwear testing

treadwear related information is

given prominent treatment in tire advertising.

Cooper and Dunlop commented that the treadwear rating should be

deleted because the testing is expensive and ``environmentally

unfriendly.'' Since treadwear is the central feature of the

statutorily-mandated UTQGS, NHTSA is not proposing to delete treadwear.

NHTSA is well aware of the expense of treadwear testing. NHTSA's

contract cost of operating a 4-car test convoy for the 7,200 mile test

(6,400 miles for the test and 800 miles for the pre-test break-in) is

$17,751. Dunlop did not disclose the basis for the $27,524.64 figure it

quoted. Regardless of the per convoy cost, the agency notes that the

per tire cost is minimal, considering that the test cost is averaged

over all the tires produced of the same type. As to greenhouse gas

emissions, NHTSA estimates that the emissions into the atmosphere per

4-car convoy is between 14.08 and 15.8 tons. Again, Dunlop did not

explain how it arrived at the 22-ton figure.

As discussed in section IIA1, Treadwear test and calculation

procedures, above, the agency believes that the primary reason for past

treadwear grade inflation has been the effects of aging on the CMTs

while in storage. The agency believes, however, that wrapping the CMTs

in polyethylene bags and storing them in a warehouse where the

temperature only varies between 60 deg. and 90 deg. is minimizing the

aging effects on the different lots of CMTs.

The agency is persuaded by the suggestions of Goodyear, Cooper,

Dunlop, BF and GT that the BCWR be fixed at its present figure, 1.47

mils per thousand. Maintaining the BCWR at the current figure would

allow existing treadwear ratings to remain essentially unchanged and

prevent future grade creep. Further, the fiscal expense and

environmental effects of running test convoys would be eliminated

The agency is persuaded by the suggestions of Goodyear, Cooper,

Dunlop, BF and GT that the BCWR be fixed at its present figure, 1.47

mils per thousand. Maintaining the BCWR at the current figure would

allow existing treadwear ratings to remain essentially unchanged and

prevent future grade creep. Further, the fiscal expense and

environmental effects of running test convoys would be eliminated.

Accordingly, NHTSA proposes to fix the BCWR of all future lots of CMTs

at the current rate of 1.47 mils per thousand, or the value in use on

the date of issuance of any final rule resulting from this proposed

rulemaking action. If the agency issues such a final rule, it would

consider taking the further step of subsequently substituting the BCWR

in use on the effective date of the final rule for the BCWR in use on

the issuance date of the final rule. The agency believes that fixing

the BCWR, in addition to the more strictly controlled storage

procedures, would eliminate or significantly reduce treadwear grade

inflation and reduce costs both to NHTSA and the industry by not having

to test each new lot of CMTs.

3. Costs and Benefits

The agency believes that assigning a fixed value to the BCWR would

reduce to insignificance, if not eliminate entirely, the inflation of

treadwear ratings. The change in storage procedures is internal to

NHTSA and will not result in any costs to tire manufacturers or

consumers. Fixing the BCWR at its present rate also would have no cost

effect on manufacturers or consumers because it involves no additional

testing, retesting or relabeling of tires. The treadwear amendments

would, however, benefit both manufacturers and the public by

simplifying the required treadwear grading of tires and by making the

treadwear grades more realistic and consistent.

B. Traction

ers. Fixing the BCWR at its present rate also would have no cost

effect on manufacturers or consumers because it involves no additional

testing, retesting or relabeling of tires. The treadwear amendments

would, however, benefit both manufacturers and the public by

simplifying the required treadwear grading of tires and by making the

treadwear grades more realistic and consistent.

B. Traction

1. Public Comments

Goodyear, Dunlop, ETRTO, GT, MTS, and BF recommended maintaining

the current traction rating method. GT and Dunlop stated that changing

the rating system could cause confusion both to consumers and to the

industry, and MTS stated that the current system produces reliable,

repeatable results.

Cooper, on the other hand, recommended changing the rating system,

arguing, without explanation, that the current system is oversimplified

and potentially misleading. Cooper argued further that the traction

numbers generated since NHTSA changed the test pads at San Angelo in

1989 are significantly lower than before the pads were changed and that

therefore there is no need for an additional traction grade level.

Specifically, Cooper cited traction tests conducted on the new skid

pads in 1992 and 1993 on 54 tires of 28 different brands from 12

different manufacturers. Cooper stated that those tests showed an

arithmetic mean of only 0.48.04 for traction coefficients

on the wet asphalt surface and 0.34.02 on the wet concrete

surface. Cooper stated that these figures showed a significantly

different statistical distribution than that cited by NHTSA in support

of the suggestion to upgrade the traction grading system. In addition,

Cooper noted that none of the 54 tires tested would qualify for NHTSA's

suggested ``AA'' traction grade. Finally, Cooper suggested that the

agency work with the ASTM F9 Committee to develop a better test method.

Only Michelin supported the suggestion that the traction grade be

upgraded

than that cited by NHTSA in support

of the suggestion to upgrade the traction grading system. In addition,

Cooper noted that none of the 54 tires tested would qualify for NHTSA's

suggested ``AA'' traction grade. Finally, Cooper suggested that the

agency work with the ASTM F9 Committee to develop a better test method.

Only Michelin supported the suggestion that the traction grade be

upgraded. Cooper and Dunlop opposed upgrading the traction rating,

arguing that it would confuse the public and increase costs to the

industry with no consequent benefit to consumers. Dunlop stated that

changes to the traction grading scheme would mean most existing tires

and those in production would need to be regraded. Although Goodyear

and ETRTO were not enthusiastic about upgrading the traction category,

they stated that if the traction grade were changed, they favored

creation of the ``AA'' category. MTS agreed that if the traction grade

were changed, ``AA'' would be the simplest and most meaningful change.

With respect to whether peak traction should be measured and added

to the traction grade, Goodyear, Michelin and MTS expressed support for

the suggestion, saying that peak traction correlates with stopping

distance and the measurements are reliable. Dunlop, Cooper, and BF

opposed the suggestion, however, contending that the majority of motor

vehicles currently on the road are not equipped with ABS. They also

contended that peak traction data are more variable than sliding

traction data and thus not so reliable.

The commenters agreed, however, that the cost of measuring peak

traction would be minimal since both peak and sliding traction values

could be measured under current test procedures, although data

retrieval systems would need to be modified.

2. Agency Decision

NHTSA does not agree with the conclusions that Cooper draws from

its figures regarding the traction coefficients of the new skid pads at

San Angelo. The agency notes that Cooper's figures are based on a

relatively small sample

ce both peak and sliding traction values

could be measured under current test procedures, although data

retrieval systems would need to be modified.

2. Agency Decision

NHTSA does not agree with the conclusions that Cooper draws from

its figures regarding the traction coefficients of the new skid pads at

San Angelo. The agency notes that Cooper's figures are based on a

relatively small sample.

NHTSA statistically analyzed larger samples. Its analysis of

traction tests of 254 candidate tires tested on the new skid pads

showed that the distribution of the traction coefficients of the tested

tires had a mean, or average, value of 0.516 on the wet asphalt surface

and 0.364 on the wet concrete surface. The standard deviation about the

mean values of this tire group was 0.029 on the wet asphalt and 0.017

on the concrete surface.

NHTSA's statistical analysis of 196 candidate tires tested on the

old skid pads showed the mean value of the traction coefficients of

those tires to be to be 0.533 on the wet asphalt surface and 0.375 on

the wet concrete surface. The standard deviation about the arithmetic

mean among this group was 0.036 on the old asphalt surface and 0.027 on

the old concrete surface. The agency believes that the difference

between the traction coefficients of the 196 tires tested on the old

skid pads and the 254 tires tested on the new skid pads may be due to

differences in the old and the new pads or differences in the tire

populations of 1989-1991 and 1992-1994. In any case, all future

traction testing will occur on the new pads since the old pads no

longer exist

face. The agency believes that the difference

between the traction coefficients of the 196 tires tested on the old

skid pads and the 254 tires tested on the new skid pads may be due to

differences in the old and the new pads or differences in the tire

populations of 1989-1991 and 1992-1994. In any case, all future

traction testing will occur on the new pads since the old pads no

longer exist.

Based on the average traction coefficient and standard deviation

values from the new pads, the agency proposes adding a fourth category,

designated as ``AA,'' to the traction grade only for tires with

traction coefficients that exceed 0.54 (representing the mean, 0.516,

and adding the standard deviation of 0.029) when tested on wet asphalt

and 0.38 (0.364, the mean, +0.017, the standard deviation) when tested

on wet concrete. Of the 254 tires tested as described above, only 8

would currently qualify for the new ``AA'' grade. The agency believes,

however, that an optional new traction rating would provide an

incentive for manufacturers to improve the traction performance of

other tire lines.

NHTSA disagrees with GT and Dunlop that providing a means for

differentiating the highest traction tires would cause confusion among

consumers. To the contrary, NHTSA believes that adding the ``AA''

rating would benefit consumers by providing them additional guidance

for choosing the proper tires to suit their individual needs.

Since upgrading traction performance to take advantage of the

``AA'' rating is optional, tire manufacturers would not necessarily

incur any additional costs. Those manufacturers that chose to use the

AA rating would be free to pass on whatever additional costs they would

incur to their customers (see discussion of costs below).

NHTSA agrees with Goodyear, Michelin and MTS that there is a

correlation between peak and sliding traction and that both values can

be considered equivalent for grading purposes

not necessarily

incur any additional costs. Those manufacturers that chose to use the

AA rating would be free to pass on whatever additional costs they would

incur to their customers (see discussion of costs below).

NHTSA agrees with Goodyear, Michelin and MTS that there is a

correlation between peak and sliding traction and that both values can

be considered equivalent for grading purposes. However, the agency is

persuaded by the comments of Dunlop, Cooper and BF that the majority of

vehicles currently on the road are not equipped with ABS. Thus, they

depend on sliding traction rather than peak traction for maximum

stopping action. Accordingly, NHTSA does not propose to include peak

traction in the traction ratings at this time.

3. Costs and Benefits

The proposed amendments to the traction grade under the UTQGS would

create an additional level of traction rating the use of which would be

optional to manufacturers. Therefore, the proposed ``AA'' traction

rating would apply only to those manufacturers who elect to produce

tires that meet the proposed ``AA'' criteria and label those tires

accordingly. As discussed in IIIB above, only 8 of the 254 tires skid-

tested by NHTSA would qualify for the proposed ``AA'' rating. The

manufacturers' costs of reworking tire molds to accommodate the new

traction rating would be minimal and would be necessary only for this

small group and only if the manufacturers of those tires opted to give

those tires the new, higher grade. The paper labels required by 49 CFR

575.104(d)(1)(i)(B)(2), however, would need to be changed to reflect

the 4-grade rating system.

C. Temperature/Rolling Resistance/Fuel Economy

rking tire molds to accommodate the new

traction rating would be minimal and would be necessary only for this

small group and only if the manufacturers of those tires opted to give

those tires the new, higher grade. The paper labels required by 49 CFR

575.104(d)(1)(i)(B)(2), however, would need to be changed to reflect

the 4-grade rating system.

C. Temperature/Rolling Resistance/Fuel Economy

1. Public Comments

All comments on the Request for Comments addressed the temperature/

rolling resistance/fuel economy issue. Nine trade and consumer

associations responded, including engineering companies and test

laboratories, 5 of which supported a rolling resistance grade and 4 of

which were opposed. Seven tire manufacturers responded, 6 of which

opposed a rolling resistance grade either as a substitute for the

temperature resistance grade or as a fourth rating category under the

UTQGS. Fourteen private citizens commented, 9 of whom supported a

rolling resistance grade, while 5 were opposed.

The members of the public and the private associations and

companies that opposed a rolling resistance grade cited various

objections to it. For example, Mr. Christopher Smith of Pennsylvania

asserted that NHTSA should not be concerned with rolling resistance

because it robs consumers of their choices. Mr. Fred Crum of California

stated that road surface ratings are more important than rolling

resistance ratings if fuel savings are to be achieved. Mr. Robert

Burns, President of the Private Brand Tire Group (PBTG) asserted that

the government should not force consumers to bear the cost of testing

and remolding a new UTQGS symbol which will be passed on to them by

manufacturers. Advocates for Highway Safety (AHS) expressed concern

that addition of a rolling resistance rating could cause consumers, for

reasons of economy, to purchase tires that have a lower overall

traction performance.

Cooper, Dunlop, Goodyear, BF and GT argued that rolling resistance

and temperature resistance are separate properties

ew UTQGS symbol which will be passed on to them by

manufacturers. Advocates for Highway Safety (AHS) expressed concern

that addition of a rolling resistance rating could cause consumers, for

reasons of economy, to purchase tires that have a lower overall

traction performance.

Cooper, Dunlop, Goodyear, BF and GT argued that rolling resistance

and temperature resistance are separate properties. They asserted that

rolling resistance measures the energy consumed by the tire, which

relates to the efficiency of the tire in converting motive power to

distance traveled, while temperature resistance relates to the ability

of the tire structure and materials to withstand the temperatures

generated by the flexing of the rubber and its reinforcing materials.

The PBTG opposed the deletion of the temperature resistance grade,

asserting that the temperature resistance characteristics of tires are

relevant to such hot climates as the American desert southwest where

tire dealers choose their tire lines on this basis.

Cooper and Dunlop stated that such desert countries as Saudi Arabia

require tires imported into their countries to be rated at least ``B''

for temperature resistance. Goodyear, on the other hand, supported the

deletion of the temperature resistance rating because, as NHTSA

discussed in the Request for Comments of April 25, 1994, the majority

of consumers pay no attention to this rating when purchasing tires.

Michelin also supported the deletion of the temperature resistance

grade, stating that the voluntary speed ratings placed on some tires by

manufacturers in accordance with SAE Recommended Practice J1561,

Laboratory Speed Test Procedure for Passenger Car Tires, adequately

represent the temperature resistance capability of the tire

onsumers pay no attention to this rating when purchasing tires.

Michelin also supported the deletion of the temperature resistance

grade, stating that the voluntary speed ratings placed on some tires by

manufacturers in accordance with SAE Recommended Practice J1561,

Laboratory Speed Test Procedure for Passenger Car Tires, adequately

represent the temperature resistance capability of the tire.

Michelin commented that vehicle manufacturers, in order to meet

fuel economy requirements, have long required their tire suppliers to

provide low rolling resistance original equipment (OE) tires, while

still imposing strict standards on treadwear, traction, and speed

durability. Michelin stated that since 1980 tire rolling resistance has

in some cases been reduced by as much as 50 percent while still

maintaining other performance characteristics. BF asserted that the

rolling resistance of OE tires is constantly being improved to meet

CAFE standards and that that technology is included in after-market

tires through standardization. Therefore, BF argued that there is no

need to establish a rolling resistance grade for the UTQGS.

NTDRA, PBTG, Goodyear, and GT argued that a rolling resistance

grade would be costly and yield little or no consumer benefit because

of lack of consumer interest. NTDRA contended that a rolling resistance

grade would constitute an unnecessary cost burden on manufacturers.

Goodyear, claiming a the lack of success of its Invicta GFE model low

rolling resistance tire, stated that there is little public interest in

low rolling resistance/fuel efficient tires because of their increased

cost. STL asserted that there are too many variables in measuring

rolling resistance to be of any consumer benefit. Goodyear, Michelin,

Dunlop and Cooper stated that even tires of the same size designation,

construction and load-carrying capacity can have different rolling

resistance characteristics

tle public interest in

low rolling resistance/fuel efficient tires because of their increased

cost. STL asserted that there are too many variables in measuring

rolling resistance to be of any consumer benefit. Goodyear, Michelin,

Dunlop and Cooper stated that even tires of the same size designation,

construction and load-carrying capacity can have different rolling

resistance characteristics. PBTG, Goodyear, GT, BF, and Dunlop argued

that rolling resistance cannot be improved without adversely affecting

treadwear and traction. Michelin disagreed with this assertion, saying

that tire manufacturers have used tire technology to reduce rolling

resistance in OE tires without adversely affecting treadwear or

traction.

Manufacturers generally agreed that there would be a difference in

production and consumer costs between grading for temperature

resistance and rolling resistance, but did not specify what such

difference might be. Goodyear stated that it costs less to test for

rolling resistance than for temperature resistance, but more tests

would probably be required. Goodyear estimated that rolling resistance

tests cost $175 per test while temperature resistance tests cost $250

per test. BF stated that it would be ``extremely expensive'' to

consumers to implement all the changes suggested by NHTSA in the

Request for Comments. GT estimated that to achieve reduced rolling

resistance without loss of the other tire properties would increase

tire costs to consumers by 15 percent, due to the increased cost of

redesigning and testing of tire lines. Goodyear asserted that a tire

designed to minimize rolling resistance may have a shorter tread life,

thereby creating the need for more tires with associated increased

energy consumption. The American Retreaders Association expressed

concern that such low rolling resistance tires may not be retreadable

onsumers by 15 percent, due to the increased cost of

redesigning and testing of tire lines. Goodyear asserted that a tire

designed to minimize rolling resistance may have a shorter tread life,

thereby creating the need for more tires with associated increased

energy consumption. The American Retreaders Association expressed

concern that such low rolling resistance tires may not be retreadable.

PBTG, Goodyear, BF, GT, Dunlop, NTDRA and Cooper asserted that the

best course of action would be for NHTSA to mount a publicity campaign

to educate the public with respect to proper tire maintenance and

encourage people to maintain proper inflation pressure, proper balance

and alignment, and obey speed limits. The commenters asserted that

those measures would have a more significant effect on reduction of

greenhouse gasses than grading tires for their rolling resistance

characteristics. Nevertheless, Dunlop, BF, Goodyear, GT, and Cooper

suggested that if NHTSA decides to proceed with the rolling resistance

grade, the agency should make the requirement effective for newly-

introduced tire lines only.

The lone manufacturer supporting the establishment of a rolling

resistance grade was Michelin. That company supported the deletion of

the temperature resistance grade, stating that it does not serve the

purpose for which it was intended and does not provide useful consumer

information. Michelin asserted, on the other hand, that establishment

of a rolling resistance grade for all tires would encourage

manufacturers to improve the rolling resistance characteristics of

replacement tires and bring them up to the capabilities of OE tires.

Michelin estimated that the additional consumer cost would be less than

$1 per tire, but in any case no more than $2.50 per tire. Michelin

believes that those costs would be more than offset by the value of the

fuel conservation and reduction of global warming gases that rolling

resistance labeling would make possible.

2. Agency Decision

a. Temperature resistance

he capabilities of OE tires.

Michelin estimated that the additional consumer cost would be less than

$1 per tire, but in any case no more than $2.50 per tire. Michelin

believes that those costs would be more than offset by the value of the

fuel conservation and reduction of global warming gases that rolling

resistance labeling would make possible.

2. Agency Decision

a. Temperature resistance. The temperature resistance grade under

the UTQGS represents a tire's ability to dissipate and withstand heat

buildup that can cause the tire to degenerate and result in a reduction

of tire life or even tire failure. Currently, 20.4 percent of new

replacement tire lines are rated A, 51.8 percent are rated B, and 26.4

percent are rated C.

The temperature resistance grade is not widely understood by

consumers and therefore most do not find it useful when purchasing

tires. NHTSA's data indicate that of consumers purchasing tires for

their own use, 38 percent have heard of the temperature resistance

grade, while only 12 percent consider it in making tire selections. The

comparable figures for the other types of ratings are 74 percent and 29

percent for the treadwear ratings and 65 and 27 percent for the

traction ratings.

As stated above, in order to create wider knowledge and better

understanding of the UTQGS ratings among consumers, including the

temperature resistance rating, NHTSA has issued consumer information

bulletins, press releases, and has required labels to be affixed to

each individual tire. These efforts seemed to arouse little public

interest and had no lasting effect. NHTSA has considered expanding its

publicity efforts into nationwide publicity campaigns, but such

publicity campaigns are very expensive. Further, based on the lack of

response to previous publicity on the subject, NHTSA has no reason to

believe that a widespread, expensive publicity campaign would produce

any more significant results than past efforts

ic

interest and had no lasting effect. NHTSA has considered expanding its

publicity efforts into nationwide publicity campaigns, but such

publicity campaigns are very expensive. Further, based on the lack of

response to previous publicity on the subject, NHTSA has no reason to

believe that a widespread, expensive publicity campaign would produce

any more significant results than past efforts. NHTSA believes that the

safety purposes of the temperature resistance grade can be essentially

met by other existing measures. The high speed performance test

specified in section S5.5 of Standard No. 109, New pneumatic tires,

assures the minimum temperature resistance performance for all

passenger car tires. That section requires that tires be tested at 75

miles per hour (mph) for 30 minutes, at 80 mph for 30 minutes, and

again at 85 mph for 30 minutes. At the end of the test, the tire must

have not less than the initial inflation pressure and must not

show the indications of damage specified in paragraph

S4.2.2.5(a) of Standard No. 109. Successful completion of this test

equates to a temperature resistance grade of ``C'' under the UTQGS.

That meets at least the minimum requirements under the UTQGS.

To accommodate those with special needs, such as law enforcement

vehicles that require tires capable of sustained high speeds or those

operating in areas of high ambient temperatures, tire speed ratings are

available. These ratings are voluntary industry ratings in accordance

with the procedures set forth in SAE-J1561. Such ratings are indicated

by symbols molded onto or into tire sidewalls which range from the

``S'' category, meaning capability of sustained speeds up to 112 mph,

to the ``Y'' category, meaning capability of sustained speeds up to 186

mph

ent temperatures, tire speed ratings are

available. These ratings are voluntary industry ratings in accordance

with the procedures set forth in SAE-J1561. Such ratings are indicated

by symbols molded onto or into tire sidewalls which range from the

``S'' category, meaning capability of sustained speeds up to 112 mph,

to the ``Y'' category, meaning capability of sustained speeds up to 186

mph. Tires above the ``S'' category would be equivalent to a UTQGS

temperature resistance rating of ``A.''

With respect to Michelin's comment, noted above, that the

manufacturers' voluntary speed ratings adequately represent the

temperature resistance capability of a tire, NHTSA has no data about

the number of consumers who know of and consider the industry speed

ratings. The agency believes, however, that consumers who need, for

reasons such as occupation or climate, tires with higher speed ratings

are motivated to obtain information about the industry speed ratings

and consider them in selecting replacement tires.

For those reasons, NHTSA proposes to delete the temperature

resistance rating from the UTQGS, substituting therefor a rolling

resistance/fuel economy rating, as discussed below. NHTSA believes that

since the UTQGS are intended to be meaningful and helpful to the tire-

buying public in selecting tires that suit their individual needs, the

agency should continue its efforts to make the UTQGS as meaningful and

helpful as possible to consumers by rating those tire characteristics

which the public understands and in which the public is interested.

b. Rolling resistance/fuel economy. Based on the public comments in

response to the agency's April 25, 1994 Request for Comments, the

agency believes that there is a direct correlation between rolling

resistance and fuel economy. Michelin commented that a 5 percent

reduction in rolling resistance results in a 1 percent fuel savings at

highway speeds, regardless of the vehicle's fuel consumption

Rolling resistance/fuel economy. Based on the public comments in

response to the agency's April 25, 1994 Request for Comments, the

agency believes that there is a direct correlation between rolling

resistance and fuel economy. Michelin commented that a 5 percent

reduction in rolling resistance results in a 1 percent fuel savings at

highway speeds, regardless of the vehicle's fuel consumption. The

agency would welcome comments on the validity of this relationship.

NHTSA also solicits comments on how the relationship would be

affected by various real-world driving conditions, such as temperature,

precipitation, vehicle speed, and road conditions, and vehicle

conditions such as wheel alignment, tire balance, and inflation

pressures. Even if that relationship would not be affected by those

conditions, NHTSA assumes that any such fuel savings would be reduced

in direct proportion to the number of tires on the vehicle that do not

have low rolling resistance. For example, under this assumption, a

vehicle equipped with 2 low rolling resistance tires and 2 tires with

rolling resistance typical of current replacement tires would achieve

only half the savings of the same vehicle equipped with 4 low rolling

resistance tires. The agency requests comment on that assumption.

The agency does not agree with the assertions of some commenters

that rolling resistance cannot be improved without detracting from the

other tire characteristics. NHTSA agrees with commenters on the Request

for Comments that although rolling resistance and temperature

resistance are separate properties, there is a correlation between

rolling resistance and heat generation. Rolling resistance contributes

to heat buildup which can ultimately result in tire failure. Thus, a

tire with lower rolling resistance will normally run cooler, and

therefore safer, than a tire with higher rolling resistance

for Comments that although rolling resistance and temperature

resistance are separate properties, there is a correlation between

rolling resistance and heat generation. Rolling resistance contributes

to heat buildup which can ultimately result in tire failure. Thus, a

tire with lower rolling resistance will normally run cooler, and

therefore safer, than a tire with higher rolling resistance. In

addition, a tire with lower rolling resistance creates less friction,

thus contributing to tire efficiency which in turn results in less fuel

consumption.

Michelin and other commenters pointed out that the rolling

resistance of OEM tires has been significantly reduced in recent years

to assist vehicle manufacturers in meeting corporate auto fuel economy

(CAFE) standards, without loss of traction or treadwear. Since the

achievement of rolling resistance reductions without adverse safety

consequences is a significant issue, NHTSA solicits more specific data

on the differences in rolling resistance and traction characteristics

between OEM and replacement tires at the manufacturers' recommended

pressures and at typical inflation pressures.

While the cheapest way of reducing rolling resistance would also

reduce traction, there are other ways, such as alternative tread

compounds, that are reasonable in cost and that may not affect

traction. Further, the UTQGS traction ratings would inform purchasers

when making a particular tire choice that would involve a reduction in

traction. Therefore, there should logically be no inherent detraction

from treadwear or traction capabilities by the production and purchase

of low rolling resistance replacement tires. Nevertheless, the agency

solicits comments on the extent to which, if at all, there is or could

be a trade-off between safety characteristics such as traction and low

rolling resistance

involve a reduction in

traction. Therefore, there should logically be no inherent detraction

from treadwear or traction capabilities by the production and purchase

of low rolling resistance replacement tires. Nevertheless, the agency

solicits comments on the extent to which, if at all, there is or could

be a trade-off between safety characteristics such as traction and low

rolling resistance. If such trade-offs do exist-- (1) to what extent

would this occur in real-world driving and vehicle conditions and

typical inflation pressures? (2) how do tire manufacturers trade off

those characteristics between OEM and replacement tires? (3) to what

extent to the trade-offs vary for the different ways of reducing

rolling resistance?

NHTSA has no data regarding Goodyear's assertion that low rolling

resistance tires may have a shorter tread life, thus requiring more

tires with associated increased energy consumption and the adverse

environmental consequences of more scrap tires for disposal. NHTSA has

not received any reports or indication that low rolling resistance OEM

tires tend to have lower treadwear grades. To the contrary, as

discussed above, treadwear grades have steadily increased over the past

several years. Nevertheless, information is requested on any

differences in treadwear ratings between OEM and replacement tires.

Several comments suggested that there was no public interest in

lower rolling resistance. This suggestion appears to be based largely

on speculation. One commenter did rely on the lack of success of its

reduced rolling resistance tire. The agency does not believe that much

reliance can be placed on that experience. When that tire was being

sold, there was no comparative information available to the public

regarding the rolling resistance of other tires.

NHTSA believes that while significant improvements have been made

in the rolling resistance of OEM tires in the last 15 years, changes in

replacement tire rolling resistance have lagged behind somewhat

hat much

reliance can be placed on that experience. When that tire was being

sold, there was no comparative information available to the public

regarding the rolling resistance of other tires.

NHTSA believes that while significant improvements have been made

in the rolling resistance of OEM tires in the last 15 years, changes in

replacement tire rolling resistance have lagged behind somewhat. The

agency has no data, and Michelin provided no specifics, regarding that

company's assertion that the rolling resistance of OEM tires has been

reduced by 50 percent since 1980. Similarly, NHTSA has no data

indicating that, as BF contended, the low rolling resistance technology

of OEM tires is being applied to replacement tires. Although that might

eventually happen, NHTSA believes that there is an equally strong

possibility that it will not. The agency would welcome data on the

amount of reduction in rolling resistance in OEM tires

since 1980 and to what extent, if any, such technology has been applied

to currently available replacement tires.

Tire manufacturers have been producing low rolling resistance OEM

tires for vehicle manufacturers since 1980 and equivalent low rolling

resistance tires are available on the replacement market to some

extent. However, comparative information on the fuel economy benefits

of such tires is not available to consumers. The agency seeks to

expedite the availability of low rolling resistance tires by

encouraging tire manufacturers to produce low rolling resistance

replacement tires and emphasize the economic and environmental

advantages of such tires in their promotional advertising. NHTSA will

also publicize the advantages of low rolling resistance tires and

encourage the public to purchase them.

NHTSA disagrees with commenters that suggested that a public

education program encouraging proper tire maintenance would result in

as much fuel conservation as requiring a rolling resistance grade

omic and environmental

advantages of such tires in their promotional advertising. NHTSA will

also publicize the advantages of low rolling resistance tires and

encourage the public to purchase them.

NHTSA disagrees with commenters that suggested that a public

education program encouraging proper tire maintenance would result in

as much fuel conservation as requiring a rolling resistance grade. The

agency is aware that a great deal of fuel is unnecessarily consumed by

improper tire maintenance, particularly improper inflation pressure.

However, the agency believes that even if the motoring public did

properly maintain all tires, there would continue to be potential fuel

savings available by reducing the rolling resistance of replacement

tires.

ARA did not explain why it thought low rolling resistance tires

would not be retreadable. In response to the ARA comment, however,

Michelin stated that low rolling resistance tires have routinely been

retreaded without any problems. NHTSA has not received any information

or complaints on this issue, which could indicate that there is no

significant problem with retreading low rolling resistance tires. The

agency also notes that it is not aware that many car tires are

currently retreaded. NHTSA would welcome comments on this issue,

however, particularly if there are problems with retreadability,

including the types and sizes of tires involved.

Some commenters stated that the rolling resistance of larger tires

is less than that of smaller tires under the same loading conditions.

For instance, Cooper commented that tire size makes a difference in

rolling resistance measurements because tire loading is not precisely

proportional to tire size. Michelin reported rolling resistance values

of 8.3 kilograms per ton to 9.8 kilograms per ton for tires in a given

tire line having the same rim diameter and aspect ratio, but of

different width

under the same loading conditions.

For instance, Cooper commented that tire size makes a difference in

rolling resistance measurements because tire loading is not precisely

proportional to tire size. Michelin reported rolling resistance values

of 8.3 kilograms per ton to 9.8 kilograms per ton for tires in a given

tire line having the same rim diameter and aspect ratio, but of

different width.

NHTSA does not believe that the variation in the rolling resistance

of different sized tires would be so great as that reported by Michelin

under the procedures of SAE J-1269. The agency believes that, as

measured under test loading conditions, rolling resistance should

remain approximately the same for all tire sizes in a tire line. If

certain tire lines do show substantial differences in rolling

resistance among sizes, testing of each size may be necessary to

determine fuel economy grades. Depending on the number of tires and

lines involved, manufacturers might choose to grade each size

individually or assign the lower value to all tires within the same

line. At the extreme, there may be two or three rolling resistance

values for a tire line, just as there is presently for temperature

resistance or treadwear.

For the reasons discussed above, the agency proposes to delete the

temperature resistance grade from the UTQGS and substitute a fuel

economy grade. The agency considers fuel economy more understandable

and more meaningful to the tire-buying public than the temperature

resistance rating. As pointed out above, the latter is not widely

understood or utilized by the public in their tire purchases. Finally,

addition of the fuel economy grade furthers the initiatives in the

Climate Change Action Plan issued by the Administration in a national

effort to reduce greenhouse gas emissions

erstandable

and more meaningful to the tire-buying public than the temperature

resistance rating. As pointed out above, the latter is not widely

understood or utilized by the public in their tire purchases. Finally,

addition of the fuel economy grade furthers the initiatives in the

Climate Change Action Plan issued by the Administration in a national

effort to reduce greenhouse gas emissions.

The agency is proposing to base the new fuel economy rating on a

rolling resistance coefficient instead of rolling resistance itself

since this will partially normalize rolling resistance variations by

tire size within a tire line. The rolling resistance coefficient

(Cr) is calculated by dividing the rolling resistance by the load

on the tire when tested in accordance with SAE J-1269. Michelin stated

that this coefficient ranges from 0.0073 to 0.0156, while Goodyear

assessed the range as being between 0.0067 and 0.0152, and STL fixed it

at 0.005 to 0.015.

Using 0.010 as the midpoint of the range, one method of rating fuel

economy based on the rolling resistance coefficient would be by rating

tires with a coefficient of less than 0.010 as ``A'' for fuel economy.

Tires with a coefficient of 0.010 to 0.015 could be graded ``B'', while

tires with a rolling resistance coefficient greater than 0.015 could be

rated ``C''. This approach would be consistent with the views of those

commenters who stated that if a rolling resistance/fuel economy rating

were established, the A, B, and C ratings would be simpler, and

therefore preferable.

Michelin, on the other hand, prefers a more differentiated,

quantitative expression of the amount of potential fuel savings than

would be provided by a general indication as in the case of the letter

ratings. The agency believes that some consumers might also prefer this

method

sistance/fuel economy rating

were established, the A, B, and C ratings would be simpler, and

therefore preferable.

Michelin, on the other hand, prefers a more differentiated,

quantitative expression of the amount of potential fuel savings than

would be provided by a general indication as in the case of the letter

ratings. The agency believes that some consumers might also prefer this

method. For example, a rolling resistance coefficient of 0.0080 would

be graded as a 9 percent increase in fuel savings (100(0.0150-0.0080)/

(0.0150)(5)) compared to a rolling resistance coefficient of 0.0150

(the number (5) in the preceding calculation represents a 5 percent

change in rolling resistance, corresponding to a 1 percent change in

fuel economy). A rolling resistance coefficient of 0.0150 or greater

would be graded as 0 percent, indicating no fuel savings.

The agency seeks to make the rolling resistance/fuel economy rating

as meaningful as possible to consumers. Accordingly, the agency

solicits comments on the feasibility and preferability of the two

methods of expressing the rating as discussed above, namely the A, B,

and C method or the method quantifying the amount of potential fuel

savings of the tire.

Note: All amendments related to the former method are identified

in the regulatory text as ``alternative 1'' and all those related to

the latter method are identified as ``alternative 2.''

3. Costs and Benefits.

The requirement to test and label all tires for rolling resistance

could add to the testing costs associated with the production of tires.

NHTSA believes that some of the costs of grading tires for rolling

resistance would be offset by the deletion of testing for temperature

resistance. Some commenters stated that although the rolling resistance

test is less costly than the temperature resistance test, tire

manufacturers may need to conduct more rolling resistance tests on

different tire sizes to determine accurate fuel economy grades

believes that some of the costs of grading tires for rolling

resistance would be offset by the deletion of testing for temperature

resistance. Some commenters stated that although the rolling resistance

test is less costly than the temperature resistance test, tire

manufacturers may need to conduct more rolling resistance tests on

different tire sizes to determine accurate fuel economy grades.

GT estimated the cost of rolling resistance testing at $250 per

test, while Goodyear estimated $175 and BF estimated $100. Considering

those comments, NHTSA believes that, as stated in the Request for

Comments of April 25, 1994, the cost of a rolling resistance test

should not exceed $250. The commenters variously estimated the cost of

rolling resistance testing machines at between $400,000 and $1.2

million. Cooper stated that if rolling resistance tests were required,

it would require a capital investment of $1.2 million to purchase 4

test machines. Considering the data submitted by commenters, NHTSA

estimates that a single tire station rolling resistance test

machine can be purchased for $500,000. NHTSA also notes,

however, that tire manufacturers have the option of contracting with

independent testing laboratories for their testing requirements,

thereby avoiding a large capital outlay.

NHTSA estimates that the costs of labeling for fuel economy would

be minimal, probably no more than pennies per tire. That conclusion is

based on Cooper's statement that its total UTQGS labeling costs are

$0.10 per tire, and Michelin's statement that its total UTQGS labeling

could cost up to $0.15 per tire. On this issue, NHTSA agrees with

Michelin that if given sufficient lead time to change tire molds during

a regular replacement cycle, the proposed labeling changes would have

negligible cost impact.

NHTSA estimates that the consumer cost of improving rolling

resistance would be no more than $5 per tire, or $20 per set of 4

tement that its total UTQGS labeling

could cost up to $0.15 per tire. On this issue, NHTSA agrees with

Michelin that if given sufficient lead time to change tire molds during

a regular replacement cycle, the proposed labeling changes would have

negligible cost impact.

NHTSA estimates that the consumer cost of improving rolling

resistance would be no more than $5 per tire, or $20 per set of 4.

However, those figures are based on the projected cost of reducing the

average rolling resistance of OEM tires by 10 percent, not on the cost

of reducing average aftermarket tires' rolling resistance values to the

level of average OEM tires. NHTSA solicits additional and more specific

comments on the cost per tire of decreasing the rolling resistance of

typical replacement tires to that of typical OEM tires, including the

magnitude of that reduction in rolling resistance (Michelin asserted

that the average rolling resistance of OEM tires is 22.6 percent lower

than that of average replacement tires) and a description of the

specific materials and design changes on which the cost estimate(s) is

based. Further, are any alternative materials or designs that would

significantly lower costs? To what extent are the answers to this

question affected by typical tire and vehicle maintenance habits by

consumers, such as inflation pressure, wheel alignment and tire

balance?

NHTSA estimates that, assuming the realization of fuel economy

gains of 4 percent, the use of 4 low rolling resistance replacement

tires on a typical passenger car could result in fuel savings of 67

gallons over an assumed 40,000 mile tread life. The present value of

such fuel savings, excluding Federal and state taxes, would be

approximately $58. The average cost-benefit ratio of fuel savings per

tire purchase would therefore be 2.9 to 1 ($58/$20) for passenger cars.

Given these assumptions, the improved rolling resistance of the tires

could in most cases pay for itself in slightly more than 1 year

an assumed 40,000 mile tread life. The present value of

such fuel savings, excluding Federal and state taxes, would be

approximately $58. The average cost-benefit ratio of fuel savings per

tire purchase would therefore be 2.9 to 1 ($58/$20) for passenger cars.

Given these assumptions, the improved rolling resistance of the tires

could in most cases pay for itself in slightly more than 1 year.

However, NHTSA notes that the imposition of rolling resistance

grading would not include any obligation for tire manufacturers to

reduce the rolling resistance of their tires. In fact, if the

manufacturers believe that there is no consumer interest in low rolling

resistance tires, they need not make any changes in their tires other

than adding the grade marking on the sidewall.

D. Lead Time

The agency is proposing to make these amendments effective one year

after issuance of the final rule. The agency believes that this would

be sufficient for the following reasons. None of the amendments would

require tire manufacturers to redesign their tires. Further, neither

the treadwear nor the traction amendments would require the retesting

of any tires. The rolling resistance/fuel economy amendments would

require the testing of all existing tires. However, the agency believes

that that testing could be readily completed in time to begin labeling

tires with rolling resistance information at the end of a year.

Several tire manufacturers urged that the rolling resistance

requirement be made effective for newly introduced tire lines only. The

agency lacks authority to establish effective dates in the requested

fashion. It could phase-in the requirement by percentage of production,

as it has various vehicle standards, or by type of tire. However, NHTSA

believes that a year should be sufficient lead time and that a phase-in

would not be necessary. Nevertheless, the agency requests comment on

these lead time issues.

IV. Rulemaking Analyses and Notices

ity to establish effective dates in the requested

fashion. It could phase-in the requirement by percentage of production,

as it has various vehicle standards, or by type of tire. However, NHTSA

believes that a year should be sufficient lead time and that a phase-in

would not be necessary. Nevertheless, the agency requests comment on

these lead time issues.

IV. Rulemaking Analyses and Notices

A. E.O. 12866 and DOT Regulatory Policies and Procedures

This notice has not been reviewed under E.O. 12866, Regulatory

Planning and Review. The agency has considered the impact of this

rulemaking action and has concluded that it is not ``significant''

under the DOT's Regulatory Policies and Procedures. The amendments

proposed in this notice are intended to make the UTQGS more meaningful

and helpful to consumers in selecting tires to meet their needs. The

amendments to the provisions regarding the treadwear and traction

ratings are intended to reduce the treadwear rating inflation

experienced in the past, and to add a traction grade category that

differentiates the highest traction tires from lower traction tires.

Neither of those testing and labeling amendments inherently involves

any additional costs either to manufacturers or to consumers. The

testing costs for a fuel economy grade would be offset by the savings

realized by not having to conduct temperature resistance testing. The

rolling resistance test is cheaper than the temperature resistance

test, but more tire sizes may need to be tested. Additional discussion

of these issues is contained in the agency's Preliminary Regulatory

Evaluation, a copy of which has been placed in the public docket with

this rulemaking action.

B. Regulatory Flexibility Act

zed by not having to conduct temperature resistance testing. The

rolling resistance test is cheaper than the temperature resistance

test, but more tire sizes may need to be tested. Additional discussion

of these issues is contained in the agency's Preliminary Regulatory

Evaluation, a copy of which has been placed in the public docket with

this rulemaking action.

B. Regulatory Flexibility Act

NHTSA has considered the impacts of this rulemaking action under

the Regulatory Flexibility Act. I hereby certify that the proposed

amendments would not have a significant economic impact on a

substantial number of small entities. Accordingly, the agency has not

prepared a preliminary regulatory flexibility analysis.

The agency believes that no passenger car tire manufacturers

qualify as small businesses. Small businesses, small organizations, and

small governmental units would be affected by this rulemaking only to

the extent that initially they may voluntarily pay as much as $5 more

per tire for low rolling resistance tires in order to obtain the fuel

savings associated with such tires.

C. National Environmental Policy Act

NHTSA has analyzed this rulemaking for purposes of the National

Environmental Policy Act and has determined that implementation of this

action would have no significant impact on the quality of the human

environment.

Rolling resistance labeling could indirectly result in some modest

environmental benefit, to the extent that such labeling encourages

consumers to buy more fuel efficient aftermarket tires. However, the

agency currently is unable to estimate the extent of any increase in

sales of such tires. For illustrative purposes, the agency estimated

the impacts that would result from 5, 10, and 15 percentage point

increases in the sales of tires with low rolling resistance (NHTSA

believes that the current market share for low rolling resistance tires

in the aftermarket is about 15 percent)

owever, the

agency currently is unable to estimate the extent of any increase in

sales of such tires. For illustrative purposes, the agency estimated

the impacts that would result from 5, 10, and 15 percentage point

increases in the sales of tires with low rolling resistance (NHTSA

believes that the current market share for low rolling resistance tires

in the aftermarket is about 15 percent). Such sales increases could

reduce fleet fuel consumption by 155, 309, and 464 million gallons,

respectively, over the assumed 40,000 mile tread lives of tires. This

range of reductions is equivalent to oil savings of 10 to 30 thousand

barrels per day. Further, such reductions in fuel consumption would

result in vehicle carbon dioxide emission reductions of approximately

1.4, 2.7, and 4.1 million metric tons over the tread

lives of the tires.

D. Federalism

NHTSA has analyzed this proposal in accordance with the principles

and criteria contained in E.O. 12612 and has determined that the

proposals in this notice do not have sufficient federalism implications

to warrant preparation of a Federalism Assessment. No state laws would

be affected.

E. Civil Justice Reform

The proposed amendments in this notice would not have any

retroactive effect. Under 49 U.S.C. 30103(b), whenever a Federal motor

vehicle safety standard is in effect, a state or political subdivision

thereof may prescribe or continue in effect a standard applicable to

the same aspect of performance of a motor vehicle only if the state's

standard is identical to the Federal standard. However, the United

States government, a state or political subdivision of a state may

prescribe a standard for a motor vehicle or motor vehicle equipment

obtained for its own use that imposes a higher performance requirement

than that required by the Federal standard. 49 U.S.C. 30161 sets forth

a procedure for judicial review of final rules establishing, amending

or revoking Federal motor vehicle safety standards

ates government, a state or political subdivision of a state may

prescribe a standard for a motor vehicle or motor vehicle equipment

obtained for its own use that imposes a higher performance requirement

than that required by the Federal standard. 49 U.S.C. 30161 sets forth

a procedure for judicial review of final rules establishing, amending

or revoking Federal motor vehicle safety standards. A petition for

reconsideration or other administrative proceedings is not required

before parties may file suit in court.

V. Comments

A. Comment Closing Date

NHTSA has determined that it is in the public interest to provide a

comment period of less than 60 days in this instance because of the

importance of the President's Climate Change Action Plan to fuel

conservation and the reduction of greenhouse gas emissions into the

environment. In addition, the Joint Conference Report on the Department

of Transportation's Fiscal Year 1995 Appropriations directed the agency

to issue a rolling resistance tire labeling rule by June 1, 1995.

B. General

Interested persons are invited to submit comments on the amendments

proposed in this rulemaking action. It is requested but not required

that any comments be submitted in 10 copies each.

Comments must not exceed 15 pages in length (49 CFR 553.21). This

limitation is intended to encourage commenters to detail their primary

arguments in concise fashion. Necessary attachments, however, may be

appended to those comments without regard to the 15-page limit.

If a commenter wishes to submit certain information under a claim

of confidentiality, 3 copies of the complete submission including the

purportedly confidential business information should be submitted to

the Chief Counsel, NHTSA at the street address shown above, and 7

copies from which the purportedly confidential information has been

expunged should be submitted to the Docket Section

mit.

If a commenter wishes to submit certain information under a claim

of confidentiality, 3 copies of the complete submission including the

purportedly confidential business information should be submitted to

the Chief Counsel, NHTSA at the street address shown above, and 7

copies from which the purportedly confidential information has been

expunged should be submitted to the Docket Section. A request for

confidentiality should be accompanied by a cover letter setting forth

the information specified in 49 CFR part 512, the agency's confidential

business information regulation.

All comments received on or before the close of business on the

comment closing date indicated above for the proposal will be

considered, and will be available to the public for examination in the

docket at the above address both before and after the closing date. To

the extent possible, comments received too late for consideration in

regard to the final rule will be considered as suggestions for further

rulemaking action. Comments on the proposal will be available for

public inspection in the docket. NHTSA will continue file relevant

information in the docket after the closing date, and it is recommended

that interested persons continue to monitor the docket for new

material.

Those persons desiring to be notified upon receipt of their

comments in the rules docket should enclose a self-addressed stamped

postcard in the envelope with their comments. Upon receiving the

comments the docket supervisor will return the postcard by mail.

List of Subjects in 49 CFR Part 575

Consumer protection, Motor vehicle safety, Reporting and

recordkeeping, Tires.

In consideration of the foregoing, 49 CFR Part 575 would be amended

as follows:

PART 575--CONSUMER INFORMATION REGULATIONS

1. The authority citation for Part 575 continues to read as

follows:

Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166;

delegation of authority at 49 CFR 1.50.

2. Section 575.104 would be amended by revising paragraphs (a);

orting and

recordkeeping, Tires.

In consideration of the foregoing, 49 CFR Part 575 would be amended

as follows:

PART 575--CONSUMER INFORMATION REGULATIONS

1. The authority citation for Part 575 continues to read as

follows:

Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166;

delegation of authority at 49 CFR 1.50.

2. Section 575.104 would be amended by revising paragraphs (a);

(d)(1)(i)(B); (d)(1)(ii); (d)(1)(iii); (d)(2)(i), and (d)(2)(ii)

introductory text; adding paragraph (d)(2)(ii)(D); revising paragraphs

(d)(2)(iii); (e)(2)(ix)(C); and (g); Table 1; and Figure 1; and in

Figure 2, by revising Part I and in Part II, by removing the paragraph

for ``Temperature'' and adding a paragraph for ``Fuel Economy''; and by

removing Table 2A and sections (i) through (l).

Sec. 575.104 Uniform tire quality grading standards.

(a) Scope. This section requires motor vehicle and tire

manufacturers and tire brand name owners to provide information

indicating the relative performance of passenger car tires in the areas

of treadwear, traction, and fuel economy.

* * * * *

(d) Requirements--(1) Information. * * *

Alternative 1 to paragraph (d)(1)(i)(B)

(i)(B) Each tire manufactured on and after the effective date of

these amendments, other than a tire sold as original equipment on a new

vehicle, shall have affixed to its tread surface so as not to be easily

removable a label or labels containing its grades and other information

in the form illustrated in Figure 2, Parts I and II. The treadwear

grade attributed to the tire shall be either imprinted or indelibly

stamped on the label containing the material in Part I of Figure 2,

directly to the right of or below the word ``TREADWEAR''. The traction

grade attributed to the tire shall be indelibly circled in an array of

the potential grade letters AA, A, B, or C, directly to the right of or

below the words ``TRACTION'' in Part I of Figure 2

attributed to the tire shall be either imprinted or indelibly

stamped on the label containing the material in Part I of Figure 2,

directly to the right of or below the word ``TREADWEAR''. The traction

grade attributed to the tire shall be indelibly circled in an array of

the potential grade letters AA, A, B, or C, directly to the right of or

below the words ``TRACTION'' in Part I of Figure 2. The fuel economy

grade attributed to the tire shall be indelibly circled in an array of

the potential grade letters A, B, or C directly to the right of or

below the words ``FUEL ECONOMY'' in Part I of Figure 2. The words

``TREADWEAR'', ``TRACTION'', and ``FUEL ECONOMY,'' in that order, may

be laid out vertically or horizontally. The text of Part II of Figure 2

may be printed in capital letters. The text of Part I and the text of

Part II of Figure 2 need not appear on the same label, but the edges of

the two texts must be positioned on the tire tread so as to be

separated by a distance of no more than one inch. If the text of Part I

and the text of Part II of Figure 2 are placed on separate labels, the

notation ``See EXPLANATION OF DOT QUALITY GRADES'' shall be added to

the bottom of the Part I text, and the words ``EXPLANATION OF DOT

QUALITY GRADES'' shall appear at the top of the Part II text. The text

of Figure 2 shall be oriented on the tire tread surface with lines of

type running perpendicular to the tread circumference. If a label

bearing a tire size designation is attached to the tire tread surface

and the tire size designation is oriented with lines of type running

perpendicular to the tread circumference, the text of

Figure 2 shall read in the same direction as the tire size designation.

ALTERNATIVE 2 TO PARAGRAPH (d)(1)(i)(B)

d surface with lines of

type running perpendicular to the tread circumference. If a label

bearing a tire size designation is attached to the tire tread surface

and the tire size designation is oriented with lines of type running

perpendicular to the tread circumference, the text of

Figure 2 shall read in the same direction as the tire size designation.

ALTERNATIVE 2 TO PARAGRAPH (d)(1)(i)(B)

(i)(B) Each tire manufactured on and after the effective date of

these amendments, other than a tire sold as original equipment on a new

vehicle, shall have affixed to its tread surface so as not to be easily

removable, a label or labels containing its grades and other

information in the form illustrated in Figure 2, Parts I and II. The

treadwear grade attributed to the tire shall be either imprinted or

indelibly stamped on the label containing the material in Part I of

Figure 2, directly to the right of or below the word ``TREADWEAR.'' The

traction grade attributed to the tire shall be indelibly circled in an

array of the potential grade letters AA, A, B, or C, directly to the

right of or below the word ``TRACTION.'' The fuel economy grade

attributed to the tire shall be either imprinted or indelibly stamped

on the label containing the material in Part I of Figure 2, directly to

the right of or below the words ``FUEL ECONOMY.'' The words

``TREADWEAR,'' ``TREADWEAR,'' and ``FUEL ECONOMY,'' in that order, may

be laid out vertically or horizontally. The text of Part II of Figure 2

may be printed in capital letters. The text of Part II of Figure 2 may

be printed in capital letters. The text of Part I and the text of Part

II of Figure 2 need not appear on the same label, but the edges of the

two texts must be positioned on the tire tread so as to be separated by

a distance of no more than one inch

y

be laid out vertically or horizontally. The text of Part II of Figure 2

may be printed in capital letters. The text of Part II of Figure 2 may

be printed in capital letters. The text of Part I and the text of Part

II of Figure 2 need not appear on the same label, but the edges of the

two texts must be positioned on the tire tread so as to be separated by

a distance of no more than one inch. If the text of Part I and the text

of Part II of Figure 2 are placed on separate labels, the notation

``See EXPLANATION OF DOT QUALITY GRADES'' shall be added to the bottom

of the Part I text, and the words ``EXPLANATION OF DOT QUALITY GRADES''

shall appear at the top of the Part II text. The text of Figure 2 shall

be oriented on the tire tread surface with lines of type running

perpendicular to the tread circumference. If a label bearing a tire

size designation is attached to the tire tread surface and the tire

size designation is oriented with lines of type running perpendicular

to the tread circumference, the text of Figure 2 shall read in the same

direction as the tire size designation.

ALTERNATIVE 1 TO PARAGRAPH (d)(1)(ii)

(ii) In the case of information required in accordance with

Sec. 575.6(c) to be furnished to prospective purchasers of motor

vehicles and tires, each vehicle manufacturer and each tire

manufacturer or brand name owner shall, as part of that information,

list all possible grades for traction and fuel economy, and restate

verbatim the explanations for each performance area specified in Figure

2. The information need not be in the same format as in Figure 2. In

the case of a tire manufacturer or brand name owner, the information

must indicate clearly and unambiguously the grade in each performance

area for each tire of that manufacturer or brand name owner offered for

sale at the particular location.

ALTERNATIVE 2 TO PARAGRAPH (d)(1)(ii)

r each performance area specified in Figure

2. The information need not be in the same format as in Figure 2. In

the case of a tire manufacturer or brand name owner, the information

must indicate clearly and unambiguously the grade in each performance

area for each tire of that manufacturer or brand name owner offered for

sale at the particular location.

ALTERNATIVE 2 TO PARAGRAPH (d)(1)(ii)

(ii) In the case of information required in accordance with

Sec. 575.6(c) to be furnished to prospective purchasers of motor

vehicles and tires, each vehicle manufacturer and each tire

manufacturer or brand name owner shall, as part of that information,

list all possible traction grades and restate verbatim the explanations

for each performance area specified in Figure 2. The information need

not be in the same format as in Figure 2. In the case of a tire

manufacturer or brand name owner, the information must indicate clearly

and unambiguously the grade in each performance area for each tire of

that manufacturer or brand name owner offered for sale at the

particular location.

ALTERNATIVE 1 TO PARAGRAPH (d)(1)(iii)

(iii) In the case of information required in accordance with

Sec. 575.6(a) to be furnished to the first purchaser of a new motor

vehicle, other than a motor vehicle equipped with tires manufactured

prior to the effective date of these amendments, each manufacturer of

motor vehicles shall, as part of the information, list all possible

grades for traction and fuel economy, and restate verbatim the

explanation for each performance area specified in Figure 2. The

information need not be in the format of Figure 2, but it must contain

a statement referring the reader to the tire sidewall for the specific

tire grades for the tires with which the vehicle is equipped.

ALTERNATIVE 1 TO PARAGRAPH (d)(1)(iii)

ation, list all possible

grades for traction and fuel economy, and restate verbatim the

explanation for each performance area specified in Figure 2. The

information need not be in the format of Figure 2, but it must contain

a statement referring the reader to the tire sidewall for the specific

tire grades for the tires with which the vehicle is equipped.

ALTERNATIVE 1 TO PARAGRAPH (d)(1)(iii)

(iii) In the case of information required in accordance with

Sec. 575.6(a) to be furnished to the first purchaser of a new motor

vehicle, other than a motor vehicle equipped with tires manufactured

prior to the effective date of these amendments, each manufacturer of

motor vehicles shall, as part of the information, list all possible

grades for traction and fuel economy, and restate verbatim the

explanation for each performance area specified in Figure 2. The

information need not be in the format of Figure 2, but it must contain

a statement referring the reader to the tire sidewall for the specific

tire grades for the tires with which the vehicle is equipped.

(2) Performance--(i) Treadwear. Each tire shall be graded for

treadwear performance with the word ``TREADWEAR'' followed by a number

of two or three digits representing the tire's grade for treadwear,

expressed as a percentage of the NHTSA nominal treadwear value, when

tested in accordance with the conditions and procedures specified in

paragraph (e) of this section. Treadwear grades shall be in multiples

of 20 (for example, 80, 120, and 160).

(ii) Traction. Each tire shall be graded for traction performance

with the word ``TRACTION,'' followed by the symbols C, B, A, or AA,

when the tire is tested in accordance with the conditions and

procedures specified in paragraph (f) of this section.

* * * * *

(D) The tire may be graded AA only when its adjusted traction

coefficient is both:

multiples

of 20 (for example, 80, 120, and 160).

(ii) Traction. Each tire shall be graded for traction performance

with the word ``TRACTION,'' followed by the symbols C, B, A, or AA,

when the tire is tested in accordance with the conditions and

procedures specified in paragraph (f) of this section.

* * * * *

(D) The tire may be graded AA only when its adjusted traction

coefficient is both:

(1) More than 0.54 when tested in accordance with paragraph (f)(2)

of this section on the asphalt surface specified in paragraph (f)(1)(i)

of this section; and

(2) More than 0.38 when tested in accordance with paragraph (f)(2)

of this section on the concrete surface specified in paragraph

(f)(1)(i) of this section.

ALTERNATIVE 1 TO PARAGRAPH (d)(2)(iii)

(iii) Fuel economy. Each tire shall be graded for fuel economy

performance with the words ``FUEL ECONOMY'' followed by the letter A,

B, or C, based on its performance when the tire is tested in accordance

with the procedures specified in paragraph (g) of this section.

(A) The tire may be graded A only if its rolling resistance

coefficient is less than 0.010.

(B) The tire may be graded B only if its rolling resistance

coefficient is equal to or greater than 0.010 but less than 0.015.

(C) The tire may be graded C if its rolling resistance coefficient

equal to or greater than 0.015.

ALTERNATIVE 2 TO PARAGRAPH (d)(2)(iii)

(iii) Fuel economy. Each tire shall be graded for fuel economy

performance with the words ``FUEL ECONOMY'' followed by

the tire's rated percentage of increase in fuel savings, such as

``5%'', based on the tire's performance when tested in accordance with

the procedures specified in paragraph (g) of this section.

* * * * *

qual to or greater than 0.015.

ALTERNATIVE 2 TO PARAGRAPH (d)(2)(iii)

(iii) Fuel economy. Each tire shall be graded for fuel economy

performance with the words ``FUEL ECONOMY'' followed by

the tire's rated percentage of increase in fuel savings, such as

``5%'', based on the tire's performance when tested in accordance with

the procedures specified in paragraph (g) of this section.

* * * * *

(e) Treadwear grading conditions and procedures. * * *

(2) Treadwear grading procedure. * * *

(ix) * * *

(C) Determine the course severity adjustment factor by assigning a

base wear rate of 1.47 to the course monitoring tires and dividing that

rate by the average wear rate for the four course monitoring tires.

* * * * *

ALTERNATIVE 1 TO PARAGRAPH (g)

(g) Fuel economy grading. The fuel economy grade is calculated as

follows:

(1) The tire's rolling resistance coefficient is determined in

accordance with the procedures of SAE Recommended Practice J-1269,

Rolling Resistance Measurement Procedure for Passenger Car, Light

Truck, and Highway Truck and Bus Tires, revised March, 1987 (SAE J-

1269).

(2) The rolling resistance coefficient (Cr) is the ratio of

rolling resistance force (Fr) to the normal load on the tire:

(Fn) or Cr=Fr Fn.

Example No 1. Fn=1,100 pounds of force (lbf); Fr=8 lbf;

then Cr=8 1,00=0.00727.

A rolling resistance coefficient of 0.00727 would result in a

grade of ``A'' for fuel economy.

Example No. 2. Fn=1,100 lbf, and Fr=18 lbf, then

Cr=18 1,100=0.01636.

A rolling resistance coefficient of 0.01636 would result in a

grade of ``C'' for fuel economy.

ALTERNATIVE 2 TO PARAGRAPH (g)

(Fn) or Cr=Fr Fn.

Example No 1. Fn=1,100 pounds of force (lbf); Fr=8 lbf;

then Cr=8 1,00=0.00727.

A rolling resistance coefficient of 0.00727 would result in a

grade of ``A'' for fuel economy.

Example No. 2. Fn=1,100 lbf, and Fr=18 lbf, then

Cr=18 1,100=0.01636.

A rolling resistance coefficient of 0.01636 would result in a

grade of ``C'' for fuel economy.

ALTERNATIVE 2 TO PARAGRAPH (g)

(g) Fuel economy grading. The fuel economy grade is calculated as

follows:

(1) The tire's rolling resistance coefficient is determined in

accordance with the procedures of SAE Recommended Practice J-1269,

Rolling Resistance Measurement Procedure for Passenger Car, Light

Truck, and Highway Truck and Bus Tires, revised March, 1987 (SAE J-

1269).

(2) The rolling resistance coefficient (Cr) is the ratio of rolling

resistance force (Fr) to the normal load on the tire: (Fn) or

Cr=FrFn.

Example No 1. Fn=1,100 pounds of force (lbf); Fr=8 lbf; then

Cr=8=1,100=0.00727.

Example No. 2. Fn=1,100 lbf, and Fr=18 lbf, then

Cr=181,100=0.01636.

(3) Determine the tire's fuel economy grade by subtracting its

rolling resistance coefficient from 0.0150, then multiply by 1,333. The

resulting number, rounded to the nearest whole number, is the fuel

economy grade, expressed as a percentage.

(i)(A) Using the numbers in Example No. 1 in paragraph (g)(2) of

this section, given the rolling resistance coefficient (Cr) of 0.00727,

the fuel economy grade (Fg) would be calculated as follows:

Fg=(0.0150-0.00727) x 1,333=(0.00773) x 1,333=10.30 percent, rounded

to 10 percent.

(B) This would represent an increase of 10 percent in fuel economy,

expressed as a fuel economy grade of ``10%''.

i)(A) Using the numbers in Example No. 1 in paragraph (g)(2) of

this section, given the rolling resistance coefficient (Cr) of 0.00727,

the fuel economy grade (Fg) would be calculated as follows:

Fg=(0.0150-0.00727) x 1,333=(0.00773) x 1,333=10.30 percent, rounded

to 10 percent.

(B) This would represent an increase of 10 percent in fuel economy,

expressed as a fuel economy grade of ``10%''.

(ii) Using the numbers in Example No. 2 in paragraph (g)(2) of

this section: If Fn=1,100 lbf, and Fr=18 lbf, then

Cr=181,100=0.01636

Fg=(0.0150-0.01636) x 1,333=(-0.00136) x 1,333 =-1.82 or 0 percent

A negative value represents a 0 percent increase in fuel economy,

and would be expressed as a fuel economy grade of ``0%''.

Table 1.--Test Inflation Pressures

(11)Max

imum

permis

sible

inflat

ion

pressu

re for

the

treadw

ear

test

----------------------------------------------------------------------------------------------------------------

(7)Tire

s

other

than

CT

tires

(3)CT

Tires

----------------------------------------------------------------------------------------------------------------

(2)Psi

(4)kPa

(3)kPa

----------------------------------------------------------------------------------------------------------------

32... 36 40 60 240 280 300 340 350 290 330 350 390

24... 28 32 52 180 220 180 220 230 230 270 230 270

* * * * *

ALTERNATIVE 1 TO FIGURE 1

BILLING CODE 4910-59-P

[GRAPHIC][TIFF OMITTED]TP24MY95.000

ALTERNATIVE 2 TO FIGURE 1:

[GRAPHIC][TIFF OMITTED]TP24MY95.001

BILLING CODE 4910-59-P

ALTERNATIVE 1 TO FIGURE 2--[PART I]

Figure 2--[Part I]--DOT Quality Grades

TREADWEAR

TRACTION AA A B C

FUEL ECONOMY A B C

ALTERNATIVE 2 TO FIGURE 2--[PART I]

TREADWEAR

TRACTION AA A B C

FUEL ECONOMY

ALTERNATIVE 1 TO FIGURE 2--[PART II]

[Part II] * * *

* * * * *

FUEL ECONOMY

C][TIFF OMITTED]TP24MY95.000

ALTERNATIVE 2 TO FIGURE 1:

[GRAPHIC][TIFF OMITTED]TP24MY95.001

BILLING CODE 4910-59-P

ALTERNATIVE 1 TO FIGURE 2--[PART I]

Figure 2--[Part I]--DOT Quality Grades

TREADWEAR

TRACTION AA A B C

FUEL ECONOMY A B C

ALTERNATIVE 2 TO FIGURE 2--[PART I]

TREADWEAR

TRACTION AA A B C

FUEL ECONOMY

ALTERNATIVE 1 TO FIGURE 2--[PART II]

[Part II] * * *

* * * * *

FUEL ECONOMY

The fuel economy grade gives a relative value of the tire's

potential to affect a motor vehicle's fuel economy. For example, a

vehicle with four tires rated ``A'' for fuel economy would have

lower rolling resistance and therefore greater fuel efficiency than

a vehicle with four tires rated ``B'' or ``C''. Saving fuel reduces

carbon dioxide emissions which contribute to global warming. It

should be noted, however, that actual fuel savings depend on driving

habits, proper vehicle and tire maintenance, proper tire inflation

pressure, road conditions, and climate. The fuel economy grade is

based on testing the tire for rolling resistance under controlled

conditions using specified test procedures. Only tires of the size

appropriate for your car should be compared.

[ALTERNATIVE 2 TO FIGURE 2--[PART II]

[Part II * * *]

* * * * *

FUEL ECONOMY

The fuel economy grade gives a relative value of the tire's

potential to affect a motor vehicle's fuel economy. For example, a

vehicle with four tires rated ``2%'' for fuel economy would achieve

2% higher fuel economy than a vehicle with four tires rated ``0%.''

A vehicle with two tires rated ``2%'' and two tires rated ``0%''

would achieve 1% higher fuel economy than a vehicle with four tires

rated ``0%.'' Saving fuel reduces carbon dioxide emissions which

contribute to global warming. It should be noted, however, that

actual fuel savings depend on driving habits, proper vehicle and

tire maintenance, proper tire inflation pressure, road conditions,

and climate

ith two tires rated ``2%'' and two tires rated ``0%''

would achieve 1% higher fuel economy than a vehicle with four tires

rated ``0%.'' Saving fuel reduces carbon dioxide emissions which

contribute to global warming. It should be noted, however, that

actual fuel savings depend on driving habits, proper vehicle and

tire maintenance, proper tire inflation pressure, road conditions,

and climate. The fuel economy grade is based on testing the tire for

rolling resistance under controlled conditions using specified test

procedures. Only tires of the size appropriate for your car should

be compared.

* * * * *

Issued on May 17, 1995.

Barry Felrice,

Associate Administrator for Safety Performance Standards.

[FR Doc. 95-12513 Filed 5-18-95; 1:52 pm]

BILLING CODE 4910-59-P