DOT (Department of Transportation) Qual-
ity Grades: All passenger car tires must
conform to federal safety requirements in
addition to these grades.
Quality grades can be found where appli-
cable on the tire sidewall between tread
shoulder and maximum section width. For
example:
Treadwear 200 Traction AA Temperature
A
Treadwear
The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when
tested under controlled conditions on a
specified government test course. For ex-
ample, a tire graded 150 would wear one
and one-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 conditions 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 and C
The traction grades, from highest to low-
est, are AA, A, B, and C. Those grades repre-
sent 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 traction perfor-
mance.
WARNING
The traction grade assigned to this tire
is based on straight-ahead braking
traction tests, and does not include ac-
celeration, cornering, hydroplaning, or
peak traction characteristics.
Temperature A, B and C
The temperature grades are A (the high-
est), B, and C, representing the tire’s resis-
tance to the generation of heat, and its
ability to dissipate heat when tested under
controlled conditions on a specified indoor
laboratory test wheel. Sustained high tem-
perature can cause the material of the tire
to degenerate and reduce tire life, and ex-
cessive temperature can lead to sudden
tire failure. The grade C corresponds to a
level of performance which all passenger
car tires must meet under the Federal Mo-
tor Vehicle Safety Standard No. 109. Grades
B and A represent higher levels of perfor-
mance on the laboratory test wheel than
the minimum required by law.
WARNING
The temperature grade for this tire is
established for a tire that is properly in-
flated and not overloaded. Excessive
speed, under-inflation, or excessive
loading, either separately or in combi-
nation, can cause heat build-up and
possible tire failure.
UNIFORM TIRE QUALITY GRADING
Technical and consumer information10-43
