For 1990-2009 cars

## Abnormal or Excessive Tire Wear Diagnosis

• | Inspect for hard or severe driving.

• | Inspect for unrotated tires.

• | Inspect for the wrong inflation pressure.

• | Inspect for broken or sagging springs.

• | Inspect for unbalanced tires.

• | Inspect for a worn strut dampener or shock absorber.

• | Inspect for an overloaded vehicle.

• | Inspect the wheel alignment.

## Abnormal or Excessive Tire Wear Scuffed

• | Inspect for excessive speed on turns.

• | Inspect for a bent or twisted suspension arm.

• | Inspect for incorrect toe.

## Abnormal or Excessive Tire Wear Cupped

• | Inspect the wheel alignment.

• | Inspect for worn strut dampeners or shock absorbers.

• | Inspect for a worn hub and bearing assembly.

• | Inspect for excessive tire or wheel runout.

• | Inspect for a worn ball joint.

• | Inspect the rack bearing preload.

## Abnormal or Excessive Tire Wear Irregular Tire Wear

1. Irregular and premature tire wear has many causes. The following are some indicators:

• | An incorrect inflation pressure (1, 2).

• | A lack of regular rotation.

• | Any irregular driving habits.

• | An improper wheel alignment.

2. If the wheel alignment is reset due to a tire wear condition, reset the toe as close to zero degrees as the specification allows.
3. Rotate the tires if the front tire wear is different from the rear tire wear.
4. Rotate the tires if an uneven wear exists across the tread of any tire.
5. Rotate the tires if the left and right front tire wear is unequal.
6. Rotate the tires if the left and right rear tire wear is unequal.
7. Check the wheel alignment if the front left and right tire wear is unequal.
8. Check the wheel alignment if the wear is uneven across the tread of any front tire.
9. Check the wheel alignment if the front tire treads have a scuffed appearance with feather edges on one side of the tread ribs or blocks.

## Abnormal or Excessive Tire Wear Tread Wear

The original equipment tires have built-in tread wear indicators (1) in order to show when the tires should be replaced. These indicators will appear at 12.7 mm (½ in) wide bands when the tire tread depth becomes 1.6 mm (2/32 in). Replace the tire when the indicators appear in two or more grooves at 3 locations.