Temperature – A, B, CThe temperature grades are A (the highest), B,and C, representing the tire’s resistance tothe generation of heat and its ability to dissipateheat when tested under controlled conditions on aspecified indoor laboratory test wheel. Sustainedhigh temperature can cause the material of the tireto degenerate and reduce tire life, and excessivetemperature can lead to sudden tire failure.The grade C corresponds to a level of performancewhich all passenger car tires must meet underthe Federal Motor Vehicle Safety StandardNo. 109. Grades B and A represent higher levelsof performance on the laboratory test wheelthan the minimum required by law. It should benoted that the temperature grade for this tireis established for a tire that is properly inflated andnot overloaded. Excessive speed, underinflation,or excessive loading, either separately or incombination, can cause heat buildup and possibletire failure.Wheel Alignment and Tire BalanceThe tires and wheels on your vehicle were alignedand balanced carefully at the factory to give you thelongest tire life and best overall performance.Adjustments to wheel alignment and tire balancing willnot be necessary on a regular basis. However, ifyou notice unusual tire wear or your vehicle pulling toone side or the other, the alignment might need tobe checked. If you notice your vehicle vibrating whendriving on a smooth road, the tires and wheelsmight need to be rebalanced. See your dealer/retailerfor proper diagnosis.Wheel ReplacementReplace any wheel that is bent, cracked or badly rustedor corroded. If wheel nuts keep coming loose, the wheel,wheel bolts and wheel nuts should be replaced. If thewheel leaks air, replace it. Some aluminum wheels cansometimes be repaired. See your GM dealer/retailer ifany of these conditions exist.Your GM dealer/retailer will know the kind of wheelyou need.Each new wheel should have the same load-carryingcapacity, diameter, width, offset and be mountedthe same way as the one it replaces.6-68
