2000 Ford Expedition Owner's Manual - Page 203

Maintenance and care The traction grade assigned to this tire is based on straight-ahead braking traction tests, and does not include acceleration, cornering, hydroplaning or peak traction characteristics. 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 a specified 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 to a level of 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. The temperature grade for this 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. SERVICING YOUR TIRES Checking the tire pressure • Use an accurate tire pressure gauge. • Check the tire pressure when tires are cold, after the vehicle has been parked for at least one hour or has been driven less than 5 km (3 miles). • Adjust tire pressure to recommended specifications found on the Certification Label. Improperly inflated tires can affect vehicle handling and can fail suddenly, possibly resulting in loss of vehicle control. Tire rotation Because your vehicle's tires perform different jobs, they often wear differently. To make sure your tires wear evenly and last longer, rotate them as indicated in the Scheduled Maintenance Guide. If you notice that the tires wear unevenly, have them checked. 203