Uniform Tire Quality Grading and TPC LabelQuality grades can be found where applicable
on the tire sidewall between tread shoulder and maximum section width. For example:
Treadwear 200 Traction AA Temperature AThe following information relates to the system
developed by the United States National Highway Traffic Safety Administration (NHTSA),
which grades tires by treadwear, traction, and temperature performance. This applies only to
vehicles sold in the United States. The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading (UTQG) system does not apply to
deep tread, winter-type snow tires, space-saver, or temporary use spare tires, tires with
nominal rim diameters of 10 to 12 inches (25 to 30 cm), or to some limited-production tires.
While the tires available on General Motors passenger cars and light trucks may vary with
respect to these grades, they must also conform to federal safety requirements and
additional General Motors Tire Performance Criteria (TPC) standards.
All Passenger Car Tires Must Conform to Federal Safety Requirements In Addition To These
Grades.TreadwearThe 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 a half (1½) 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
AA, A, B, 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 asphalt and concrete. A tire marked C may have poor traction
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, CThe temperature grades are A (the highest), B, and C,
representing the tire's resistance 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 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 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 established for a tire that is properly inflated
and not overloaded. Excessive speed, underinflation, or excessive loading, either separately
or in combination, can cause heat buildup and possible tire failure.
Tire Quality Grading