PRACTICAL INFORMATION
109
WARNING
•Exceeding the permissible axle weight, gross vehicle weight, or any other weightrating limits can cause tire overheatingresulting in permanent deformation orcatastrophic failure.
• Do not use replacement tires with lowerload carrying capacities than the tires thatwere original equipment on the vehiclebecause this will lower the vehicle's GVWrating. Use only tires with the correct loadcarrying capacity. Consult your Volvoretailer for information.
Related information
• Label information (p. 162)
• Weights (p. 167)
Uniform Tire Quality Grading
ALL PASSENGER VEHICLE TIRES MUST CONFORM TO FEDERAL SAFETY REQUIRE-MENTS IN ADDITION TO THESE GRADES .
Quality grades can be found, where applica- ble, on the tire sidewall between the treadshoulder and maximum section width. Forexample: Treadwear 200 Traction AA Temperature A
TREADWEARThe treadwear grade is a comparative rating based on the wear rate of the tire when testedunder controlled conditions on a specified gov-ernment test course. For example, a tire graded150 would wear one and one half (1 ½) times aswell on the government course as a tire graded100. The relative performance of tires dependsupon the actual conditions of their use, however,and many depart significantly from the norm dueto variation in driving habits, maintenance practi-ces and differences in road characteristics andclimate.
TRACTIONThe traction grades, from highest to lowest, areAA, A, B, and C, as measured under controlledconditions on specified government test surfacesof asphalt and concrete. A tire marked C mayhave poor traction performance. The tractiongrade assigned to this tire is based on braking (straight-ahead) traction tests and is not a meas-ure of cornering (turning) traction.
WARNING
The traction grade assigned to this tire is based on braking (straight-ahead) tractiontests and is not a measure of cornering (turn-ing) traction.
TEMPERATUREThe temperature grades are A (the highest), B, and C, representing the tire's resistance to thegeneration of heat and its ability to dissipate heatwhen tested under controlled conditions on aspecified indoor laboratory test wheel. Sustainedhigh temperature can cause the material of thetire to degenerate and reduce tire life, and exces-sive temperature can lead to sudden tire failure.The grade C corresponds to a minimum level ofperformance that all passenger vehicle tires mustmeet under the Federal Motor Safety StandardNo. 109. Grades B and A represent higher levelsof performance on the laboratory test wheel thanthe minimum required by law.
WARNING
The temperature grade for this tire is estab- lished for a tire that is properly inflated andnot overloaded. Excessive speed, under-infla-tion, or excessive loading, either separately orin combination, can cause heat buildup andtire failure.
