CAMPAIGN: SOFT LOWER CONTROL ARM ATTACHMENT NUTS

Models: 1991 S/T Trucks built at Shreveport Assembly Plant

General Motors of Canada has determined that a defect which relates to motor vehicle safety exists in certain 1991 S/T trucks built at the Shreveport Assembly Plant. These trucks may have nuts, used to attach the lower control arms, rear spring and shackle, and rear shock absorbers, which do not meet specifications. It is possible for the nut to "strip" prior to or at the specified torque, resulting in a loss of clamp load. If clamp load were lost on a lower control arm attachment, the arm could detach, resulting in loss of vehicle control and a vehicle crash without prior warning.

To prevent this condition from occurring, dealers will replace all of the suspect lower control arm attachment nuts. Additionally, for customer satisfaction, all of the suspect rear spring and shackle and rear shock absorber nuts will be replaced.

VEHICLES INVOLVED:

Involved are certain 1991 S/T Trucks built at the Shreveport Assembly Plant (built 8/6/90). Involved VINs are listed below :

1GNCT18Z8M8180355

All affected vehicles have been identified by the VIN listing provided to involved Dealers with this bulletin. Any Dealer not receiving a listing was not shipped any of die affected vehicles.

DEALER CAMPAIGN RESPONSIBILITY:

Dealers are to service all vehicles subject to this campaign at no charge to owners, regardless of miles, age of vehicle, or ownership, from this time forward.

Whenever a vehicle subject to this campaign is taken into your new or used vehicle inventory, or it is in your dealership for service, you are to ensure the campaign correction has been made before selling or releasing the vehicle.

Owners of vehicles recently sold from your new vehicle inventory are to be contacted by the dealer, and arrangements made to make the required modification according to instructions contained in this bulletin.

CAMPAIGN PROCEDURE:

Refer to Section 4 of the Service Policies and Procedures Manual for the detailed procedure on handling Product Campaigns. Dealers are requested to complete the campaign on all transfers as soon as possible.

OWNER NOTIFICATION:

All owners of record at the time of campaign release are shown on the attached computer listing and have been notified by first class mail from General Motors. The listings provided are for campaign activity only and should not be used for any other purpose.

PARTS INFORMATION:

Parts required to complete this campaign should be ordered through regular channels, as follows

Part Number Description Quantity/Vehicle ------------ ----------- ---------------- 11500748 Nut T Truck = 12

PARTS AND LABOUR CLAIM INFORMATION:

Credit for the campaign work performed will be paid upon receipt of a properly completed campaign claim card or DCS transmission in accordance with the following:

Repair Code Description Time Allowance ----------- ------------------ ------------ 2A Remove and Replace ALL Involved Nuts .8 - T Truck

Time allowance includes 0.1 hour for dealer administrative detail associated with this campaign. Parts credit will be based on dealer net plus 30% to cover parts handling.

SERVICE PROCEDURE:

1. Raise the vehicle on a hoist.

2. Identify the type of front and rear suspension, and using Figures 1 and 2 replace the identified fasteners one at a time.

NOTE: DO NOT REMOVE ALL IDENTIFIED FASTENERS AT ONCE. THIS MAY CAUSE A CHANGE IN SUSPENSION ADJUSTMENT.

3. Install "Campaign Identification Label."

INSTALLATION OF CAMPAIGN IDENTIFICATION LABEL

Clean surface of radiator upper mounting panel and apply a Campaign Identification Label. Make sure the correct campaign number is inserted on the label. This will indicate that the campaign has been completed.

Dear General Motors Customer:

General Motors of Canada has determined that a defect which relates to motor vehicle safety exists in certain 1991 S/T trucks built at the Shreveport Assembly Plant. These trucks may have nuts, used to attach the lower control arms, rear spring and shackle, and rear shock absorbers, which do not meet specifications. It is possible for the nut to "strip" prior to or at the specified torque, resulting in a loss of clamp load. If clamp load were lost on a lower control arm attachment, there could be eventual loss of attachment, resulting in loss of vehicle control and a vehicle crash without prior warning.

To prevent this condition from occurring, your GM dealer will replace all of the suspect lower control arm attachment nuts. Additionally, all of the suspect rear spring and shackle and rear shock absorber nuts will be replaced. This service will be completed at no charge.

Please contact your GM dealer as soon as possible to arrange a service date.

This letter identifies your vehicle. Presentation of this letter to your dealer will assist their Service personnel in completing the necessary correction to your vehicle in the shortest possible time.

Further assistance, if required, may be obtained from our Customer Assistance Centre, toll free, by calling 1-800-263-3777, or if you live in Quebec, 1-800-263-7854.

We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.