Component Tests and General Diagnostics

Irregular and premature tire wear has many causes, the most common being incorrect cold tire inflation pressure, incorrect wheel alignment, lack of tire rotation and worn suspension parts. These conditions can often be diagnosed by visually inspecting the tire tread for the following telltale symptoms:

INCORRECT COLD TIRE INFLATION PRESSURE





Tread wear at center of tire (over-inflation).
- Frequent, aggressive acceleration.
- Cold tire inflation pressure too high.





Tread wear on edges of tire (under-inflation).
- Hard cornering.
- Cold tire inflation pressure too low.
- Lack of rotation.

INCORRECT WHEEL ALIGNMENT





- Tread is worn on one side of the tire more than the other.
- Tread blocks have scuffed, feathered or cupped appearance.

LACK OF TIRE ROTATION
Front tires worn more than rear tires.

WHEEL/TIRE IMBALANCE

WORN SUSPENSION PARTS
- Wheel bearing looseness.
- Front suspension loose/worn.
- Steering parts loose/worn.
- Front control arm ball stud or bushing loose or worn.
- Strut dampers worn or damaged.

TREAD WEAR INDICATORS





The original equipment tires specified for Saturn vehicles have built in tread wear indicators to warn when tires need replacement. These indicators are wide bands located beneath the tread surface at the maximum tread wear depth. Tires are determined to be worn when the indicator band appears across two or more tread grooves, at three locations about the circumference of the tire.