And the 15 is the size of the wheel it's designed for. So, in this case you've got a 31-inch tall tire for a 15-inch wheel. You know the wheel radius is 7.5-inches, and the tire radius is 15.5 inches.

It can cost between $50 for a two-wheel alignment to around $170 for a full four-wheel alignment. Signs you need an alignment include car damage, steering issues, strange noises or uneven wear on ...

A modern wheel alignment service, on the other hand, involves parking the car on a special type of rack or lift and attaching sensors to each of the four wheels.

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