Alignment/Tires - Vehicle Drift/Abnormal Tire Wear
File In Section: 3 - Steering/SuspensionBulletin No.: 81-31-02
Date: July, 1998
Subject:
Vehicle Drifts/Leads to the Right and/or Front Tire Inner Shoulder Wear (Rotate/Replace Tires, Reset Alignment)
Models:
1997-98 Cadillac Catera - Built Prior to VIN 195189
Condition
Some owners may comment that their vehicle exhibits a drift or lead to the right condition and/or a front tire inner shoulder wear condition.
Cause
The drift/lead right condition may be due to the front end alignment setting and/or the tires. The front tire inner shoulder wear condition may be due to the front end alignment setting.
Correction
The following procedure should be used to address one or both of these conditions. The following wheel alignment specifications are released for Service only; production alignment specifications may vary. The alignment should be made with the vehicle at curb weight (full tank of gas and no additional weight in car). These revised alignment specifications, which increase positive toe-in (introduced into production at VIN breakpoint WR021457) and decrease negative camber (introduced into production at VIN breakpoint WR195189), are intended to improve front tire inner shoulder wear.
A new tire (introduced into production at VIN breakpoint WR183651) is available through Goodyear. This new tire has the tread pattern reversed to eliminate a drift/lead right condition. Use only the alignment specifications in chart "A" with these new tires. Do not use the biased camber specifications from chart "B" with these new tires.
I. Inner Shoulder Wear on Front Tires Only (No Drift/Lead Right Condition)
Set the alignment to the revised specifications shown in chart "A". Additionally, if the front tires show only a modest amount of wear and are not causing a noise or handling concern, rotate the tires to equalize wear among all four tires. Also, advise the customer to rotate tires on a regular basis as recommended in the maintenance schedule to maximize tire life. However, if the front tires are exhibiting a significant amount of cupping or inner shoulder wear and/or are causing a noise or handling concern, replace the two front tires and set the alignment to the revised specifications shown in chart "A".
II. Inner Shoulder Wear on Front Tires Combined With a Drift/Lead Condition
If only modest wear is evident, rotate the tires and set the alignment to the specifications shown in chart "A", with the front camber biased as shown in chart "B". If the front tires are exhibiting a significant amount of cupping or inner shoulder wear and/or are causing a noise or handling concern, and the customer is commenting on a drift to the right, replace all four tires with the new tires and set the alignment to the revised specifications shown in chart "A".
III. Drift/Lead Right Only (No Tire Wear Condition)
If the customer comments that the vehicle drifts to the right and no excessive tire wear is apparent, set the alignment to the specifications shown in chart "A", with the front camber biased as shown in chart "B".
Obtaining New Design Tires
New tires for warranty purposes can be obtained through Goodyear Tire company's existing distribution system by requesting product code 732-367-172-OW. This tire can be identified by the designation T4ERW within the D.O.T Code on the side of the tire. Original tires had the designation T4ERD within the D.O.T. Code.
If a problem is encountered in obtaining tires, call the Goodyear Tire Assistance Number (1-888-637-3784) for assistance. In all instances, a GM Tire Requisition and return Document must be completed and given to the local Goodyear Tire dealer to obtain tires. This document is attached. Additional copies of this form should be made locally at your dealership as needed. Old tires should be returned to Goodyear.
Warranty Information
For vehicles repaired under warranty, use the table.