1996 Chevrolet Monte Carlo Owner's Manual - Page 249

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. Warning: The traction grade assigned to this tire is based on braking (straightahead) traction tests and does not include cornering (turning) traction. Temperature A, B, C The 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 aspecified 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 a level of to 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. this Warning: The temperature grade for 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. - Tread wear The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified governmenttest course. For example, a tire graded 150 would wear one and a half ( I 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, servicepractices and differences in road characteristics and climate. Traction A, B, C The traction grades, from highest to lowest, are A, B, and C, and they represent the tire's ability to stopon wet pavement as measured under controlled conditions on of specified government test surfaces asphalt and concrete. A tire marked C may have poor traction performance. -