Volvo 2003 XC70 Owner's Manual - Uniform Tire Quality Grading

2003 VOLVO XC70

Uniform tire quality grading

ALL PASSENGER CAR TIRES MUST CONFORM TO FEDERAL SAFETY REQUIREMENTS 

IN ADDITION TO THESE GRADES

Quality grades can be found, where applicable, on the tire sidewall between the 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 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 many depart 

significantly from the norm due to variation in driving habits, service practices and differences in road 

characteristics and climate.

TRACTION

The traction grades, from highest to lowest, are AA, A, B, and C, as measured under controlled 

conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have 

poor traction performance. 

WARNING! 

The traction grade assigned to this tire is based on braking (straight-ahead) traction tests and is not a 

measure of cornering (turning) traction. 

TEMPERATURE

The temperature grades are AA (the highest), A, 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 minimum 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. 

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