Things you should know about rear drive, 

front drive tire rotation, edge wear, and

" Cupping"

Tire Rotation

• Tires should be rotated every 5,000 miles if your tires are the same size all the way around. Wheels are cambered differently front and back and rotating them insures more even wear and the longest life possible for your rubber. Because tires perform different functions depending on their position on the vehicle, tire rotation is important in keeping even wear on all four tires. The proper method of rotating tires depends on whether your vehicle is front, rear, or four-wheel drive, as well as whether your tires are directional. Also make certain that the tires being rotated are of the same dimensions. If you aren't sure, consult a mechanic or tire specialist. Refer to the diagram below to determine the best rotation scheme for your vehicle:

Edge wear

• Edge can be caused by two factors, over-inflation and poor alignment. Poor alignment is the most likely cause. New cars require sophisticated alignment equipment and highly trained technicians but the cost of having your car perfectly aligned will save many times the cost in wear on tires and other parts.

Cupping

• Poorly balanced tires will hop as they turn. This hopping will cause uneven wear spots on the tire called cupping. Cupped tires soften still have plenty of tread but will develop such noise and vibration that you'll have to replace the tire prematurely.