For 1990-2009 cars

Wheel alignment refers to the angular relationship between the wheels, the suspension attaching parts, and the ground. The angle of the knuckle away from vertical view (when viewed from front of the vehicle) and the tilt of the suspension members from vertical (when viewed from the side of the vehicle) are involved in alignment.

A complete wheel alignment check should be performed when a service check is deemed necessary. A complete wheel alignment includes the measurement of all four wheels. Four wheel alignment assures that all four wheels will be running in precisely the same direction.

When the vehicle is geometrically in alignment, fuel economy and tire life are increased and steering and performance are maximized.