GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2008 🢒 G8 🢒 General Information 🢒 Vibration Diagnosis and Correction 🢒 Tire Diagnosis - Irregular or Premature Wear

Tyre Wear
Object Number: 386773 Size: SF
(1)Under-Inflation, Hard Cornering, Lack of Regular Rotation
(2)Incorrect Wheel Alignment, Hard Cornering, Lack of Regular Rotation
(3)Incorrect Wheel Alignment, Shock Absorber Failure
(4)Over-Inflation, Heavy Acceleration, Lack of Regular Rotation
(5)Normal Wear to wear indicator

Inspection Procedure
  1. Inspect front tyres for wear and damage.
  2. Inspect rear tyres for wear and damage.
  3. Rotate the tyre and wheel assembly if any of the following conditions exist:
    4. • The amount of time or distance since the last tyre rotation matches the maintenance schedule.
    • The outer tread blocks are worn more than the middle tread blocks (1).
    • The outer tread blocks are worn more than the inner tread blocks (2).
    • The middle tread blocks are worn more than the outer tread blocks (4).
  4. Measure the wheel alignment. Refer to Wheel Alignment Measurement . If any of the following conditions exist:
    5. • The tread blocks have feather edges (3).
    • The outer tread blocks are worn more than the inner tread blocks (2).
    • The inner tread blocks are worn more than the outer tread blocks (4).
  5. Inspect the struts or the shock absorbers if the tyre tread exhibits a cupped appearance (3).