Premature and/or Irregular Tire Wear (Set Front Sum Toe and Rotate Tires as Necessary)

This bulletin is being revised to add a model year and delete an Important statement regarding tire returns. Please discard Corporate Bulletin Number 05-03-07-001A (Section 03 - Suspension).

Some customers may comment on premature and/or irregular tire wear on the inside edge of the tire.

This condition may be caused by a negative front total toe (sum toe) that is outside of wheel alignment specifications.

Verify the concern and adjust the front total toe as necessary to the new preferred setting of (+0.20° ± 0.20°) for tire wear issues. Refer to the service procedure in this bulletin.

1. Check all tire pressure readings and record this information on the repair order.
2. Inspect all four tires for any premature, irregular or excessive tire wear. Refer to "Tire Diagnosis - Irregular or Premature Wear" in the Suspension section of the 2003, 2004, or 2005 Saturn ION Service Manual, Vol. 1 (SI Document ID #408063).

•	If the inside edge of the tire is worn to the wear indicators, replace the affected tire(s) and continue with the next step. Refer to "Tire Mounting and Dismounting" in the Suspension section of the appropriate model year Saturn ION Service Manual, Vol. 1 (SI Document ID# 867667).

•	If the inside edge of the tire is not worn to the wear indicators, rotate the tires and continue with the next step. Refer to "Tire Rotation" in the Suspension section of the appropriate model year Saturn ION Service Manual, Vol. 1 (SI Document ID# 1471789).

3. Set the tire inflation pressure per the vehicle tire placard on the driver’s door.
4. Inspect the fuel level. The fuel tank should be full or the vehicle should have compensating load added.

Important: A printout from the alignment machine of "before" and "after" specifications must be attached to the hardcopy of the CSO.

5. Measure the front and rear alignment angles and record the readings. Refer to "Measuring Wheel Alignment" in the Suspension section of the appropriate model year Saturn ION Service Manual, Vol. 1 (SI Document ID# 1477528 for 2003-2005 vehicles or SI Document ID# 1612978 for 2006 vehicles).

Important: When performing adjustments to vehicles requiring a 4-wheel alignment, set the rear wheel alignment angles first in order to obtain proper front alignment angles.

Important: The service equipment used to measure wheel alignment may or may not contain the correct alignment specifications for Saturn ION vehicles. Use only the settings in the Wheel Alignment Specifications chart (SI Document ID# 879951 for 2003-2005 vehicles or SI Document ID# 1619389 for 2006 vehicles) when checking and adjusting wheel alignment angles on Saturn ION vehicles.

6. If any alignment angle is outside of specification, then adjust the angle or angles until they are within vehicle specifications. Refer to Wheel Alignment Specifications chart (SI Document ID# 879951 for 2003-2005 vehicles or SI Document ID# 1619389 for 2006 vehicles).
7. Adjust front total toe to the new preferred setting (+0.20° ± 0.20°) for tire wear issues. Refer to "Front Toe Adjustment" in the Suspension section of the appropriate model year Saturn ION Service Manual, Vol. 1 (SI Document ID# 867665).
8. Road test the vehicle in order to verify the steering wheel is straight.

U.S. Retailers: To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System for E2000 (Toe, Front - Adjust) or E2020 (Wheel Alignment - Check and/or Adjust). If the tire replacement is necessary due to the inside edge of the tire being worn to the wear indicators, use the appropriate tire replacement labor and relate it to either E2000 or E2020. Tires are to be returned to the tire manufacturer.

Important: A printout from the alignment machine of "before" and "after" specifications must be attached to the hardcopy of the CSO.

Canadian Retailers: To receive credit for this repair during the warranty coverage period, submit a claim through the normal procedures for E2000 (Toe, Front - Adjust) or E2020 (Wheel Alignment - Check and/or Adjust). NOTE: Refer to Home Office Letter 1997-070 for guidelines on usage of E2000 and E2020. If the tire replacement is necessary due to the inside edge of the tire being worn to the wear indicators, refer to bulletin 01-03-10-003B for tire handling procedures.

Important: A printout from the alignment machine of "before" and "after" specifications must be attached to the hardcopy of the CSO.