Toyota 2003 MR2 Spyder Owner's Manual page 156

03 07.07
—Uniform tire quality grading
This information has been prepared
in accordance with regulations issued
by the National Highway Traffic Safe-
ty Administration of the U.S. Depart-
ment of Transportation. It provides
the purchasers and/or prospective
purchasers of Toyota vehicles with in-
formation on uniform tire quality grad-
ing.
Your Toyota dealer will help answer
any questions you may have as you
read this information.
DOT quality grades—All passenger
vehicle tires must conform to Fed-
eral Safety Requirements in addi-
tion to these grades. Quality
grades can be found where appli-
cable on the tire sidewall between
tread shoulder and maximum sec-
tion width. For example: Treadwear
200 Traction AA Temperature A.
144
Treadwear—The tread wear grade is
a comparative rating based on the
wear rate of the tire when tested un-
der controlled conditions on a speci-
fied government test course. For ex-
ample, a tire graded 150 would wear
one and a half (1–1/2) times as well
on the government course as a tire
graded 100. The relative performance
of tires depends upon the actual con-
ditions of their use, however, and may
depart significantly from the norm due
to variations in driving habits, service
practices and differences in road
characteristics and climate.
Traction AA, A, B, C—The traction
grades, from highest to lowest, are
AA, A, B, and C, and they represent
the tire's ability to stop on wet pave-
ment as measured under controlled
conditions on specified government
test surfaces of asphalt and concrete.
A tire marked C may have poor trac-
tion performance.
Warning: The traction grade assigned
to this tire is based on braking
(straight ahead) traction tests and
does not include cornering (turning)
traction.
Temperature A, B, C—The tempera-
ture grades are A (the highest), B,
and C, representing the tire's resist-
ance to the generation of heat and its
ability to dissipate heat when tested
under controlled conditions on a spe-
cified indoor laboratory test wheel.
Sustained high temperature can
cause the material of the tire to de-
generate and reduce tire life, and ex-
cessive temperature can lead to sud-
den tire failure. The
corresponds to a level of performance
which all passenger car tires must
meet under the Federal Motor Vehicle
Safety Standard No.109. Grades B
and A represent higher levels of per-
formance on the laboratory test wheel
than the minimum required by law.
2003 MR2 from Aug. '03 Prod. (OM17511U)
grade C