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uuChecking and Maintaining TiresuDOT Tire Quality Grading (U.S. Vehicles)
Continued
Maintenance
DOT Tire Quality Grading (U.S. Vehicles)The tires on your vehicle meet all U.S. Federal Safety
Requirements. All tires are also graded for treadwear, traction,
and temperature performance according to Department of
Transportation (DOT) standards. The following explains these
gradings.
Quality grades can be found where applicable on the tire sidewall
between tread shoulder and maximum section width.
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 example, 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.■
Uniform Tire Quality Grading
■
Treadwear
1Uniform Tire Quality GradingFor example:
Treadwear 200
Traction AA
Temperature A
All passenger car tires must conform
to Federal Safety Requirements in
addition to these grades.
