DOT (Department Of Transportation) Qual-
ity Grades: All passenger car tires must con-
form to federal 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 section width. For
example:
Treadwear 200 Traction AA Temperature A
TREADWEAR
The treadwear grade is a comparative rating
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 govern-
ment course as a tire graded 100. The rela-
tive performance of tires depends upon ac-
tual conditions of their use, however, and
may depart significantly from the norm due
to variations in driving habits, service prac-
tices and differences in road characteristics
and climate.
TRACTION AA, A, B AND C
The traction grades, from highest to lowest,
are AA, A, B and C. Those grades represent
the tire’s ability to stop on wet pavement as
measured under controlled conditions on
specified government test surfaces of as-
phalt and concrete. A tire marked C may have
poor traction performance.
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
TEMPERATURE A, B AND C
The temperature grades A (the highest), B,
and C, representing the tire’s resistance to
the generation of heat and its ability to dissi-
pate heat when tested under controlled con-
ditions on a specified indoor laboratory test
wheel. Sustained high temperature can cause
the material of the tire to degenerate and
reduce tire life, and excessive 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 Motor Vehicle Safety Standard No.
109. Grades B and A represent higher levels
of performance on the laboratory test wheel
than the minimum required by law.
WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, under-
inflation, or excessive loading, either sepa-
rately or in combination, can cause heat
build-up and possible tire failure.
UNIFORM TIRE QUALITY GRADING
10-16Technical information
