1996 Oldsmobile 88 Owner's Manual - Page 273

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, atire graded 150 would wearone and a 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 conditionsof their use, however, and may depart significantly from the normdue to variations in driving habits, service practices and differences in road characteristics and climate. Traction Temperature -- A, B, C -- A, B, C The temperature grades are (the highest),B, and C , A representing the tire's resistance to the generation of heat andits ability to dissipate heat when tested under controlled conditionson a specified indoor laboratory test wheel. Sustained high temperature cause the can material of the tire to degenerate and reduce tire and life, excessive temperature lead to sudden tire failure. can The grade C corresponds to level of performance a which all passenger car tires must meet under the Federal MotorVehicle Safety StandardNo. 109. Grades B and A represent higher levels performance onthe of laboratory test wheel than minimum required law. the by Warning: The temperature gradefor this tireis 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. The traction grades, from highest to lowest, are B, and A, C, and they 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 performance. Warning: The traction grade assigned to this is based tire on braking (straightahead) traction tests and does not include cornering (turning) traction. Wheel Alignment and Tire Balance The wheels on your vehicle were aligned and balanced carefully at the factory give you the longest tire to life and best overall performance. 6-41