1998 Oldsmobile 88 Owner's Manual - Page 269

Treadwear The treadwear grade is a comparative rating based on the wearrate of the tire when tested under controlled conditions on a specified government test course. 150 For example, a tire graded would wear one and a half (1 1/2) times as well on the government course 100. The relative performance of tires as a tire graded depends upon the actual conditions their use, of however, and may depart significantly from the norm due to variations in driving habits, service practices and differencesin road characteristics and climate. 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 and life, excessive temperature can lead to sudden tire failure. of The gradeC corresponds to a level Performance which all passenger car tires must meet under the No. Federal Motor Vehicle Safety Standard 109. Grades B and A represent higher levels performance onthe of laboratory test wheel than the minimum required by law. Warning: The temperature grade this tire is for established for a tire that is properly inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either separately in combination, or can cause heat buildup and possible tire failure. Traction A, B, C The traction grades,from highest to lowest, are B, A, and C, and they representthe tire's ability to stop on wet pavement as measured under controlled conditions Wheel Alignment and Tire Balance on specified government test surfaces asphalt of The wheels on your vehicle were aligned and balanced and concrete.A tire marked C may have poor life traction performance. carefully atthe factory to give you the longest tire Warning: The traction grade assigned to this tire is based and best overall performance. Scheduled wheel alignment and wheel balancing are not on braking (straight ahead) traction tests and does not needed. However, if you notice unusual tire wear or include cornering (turning) traction. your vehicle pulling one way or the other, the alignment Temperature A, B, C If may need to be reset. you notice your vehicle vibrating when driving on a smooth road, your wheels The temperature grades are (the highest),B, and C, A may need to be rebalanced. representing the tire's resistance to the generation of -- -- 6-40