CAMPAIGN: WHEEL LUG NUT TORQUE REPAIR PROCEDURE
Models: 1988 Grand Prix
TO: ALL GENERAL MOTORS DEALERS
DEFECT INVOLVED:
General Motors of Canada has determined that a defect which relates to motor vehicle safety may exist in certain 1988 Pontiac Grand Prix Model vehicles. These vehicles could have been assembled with wheel lug nuts not installed to specified torque. This condition could allow the lug nuts to loosen and/or come off the wheel studs. If this condition went unnoticed, it could eventually result in the wheel separating from the vehicle. Separation of a wheel from the vehicle could cause loss of vehicle control and a vehicle crash could occur.
To prevent the possibility of this condition occurring, Dealers will inspect all involved vehicles to assure proper wheel nut torque. If lug nuts are loose or missing, they are to be replaced, along with the wheel studs, according to the instructions included in this bulletin.
VEHICLES INVOLVED:
Involved are certain 1988 Pontiac Grand Prix Model vehicles produced within the following VIN breakpoints:
Plant From Through ----- ---- ------- Fairfax JF200067 JF208436
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 the affected vehicles.
DEALER CAMPAIGN RESPONSIBILITY:
Dealers are to service all vehicles subject to this campaign at no charge to owners, regardless of mileage, 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 in the future, you should take the steps necessary to be sure the campaign correction has been made before reselling 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 should be ordered through regular channels as follows:
Part Quantity/ Number Description Vehicle ------ ----------- -------- 9590474 Bolt - Front Wheel 12 x 1.5 x 36 (Front Only) As Req. 9590476 Bolt - Rear Stud 12 X 1.5 X 43 (Rear Only) As Req. 10028615 Nut - Wheel (For Aluminum Wheel) As Req. 10052084 Nut - Wheel (For Styled Steel Wheel) As Req. 9590477 Nut - Wheel (For Base Steel Wheel) As Req. 14102446 Cap - Wheel Nut (For Aluminum or Styled Steel Wheel) As Req.
Note: Wheel nut caps are not used on base steel wheels.
PARTS AND LABOUR CLAIM INFORMATION:
Credit for the campaign work performed will be paid upon receipt of a properly completed campaign claim card, RAPID terminal or DCS transmission in accordance with the following:
Repair Code Description Time Allowance ----------- ----------- -------------- 1A Re-torque Lug Nuts Only .4
2A Re-torque Lug Nuts - .6 Vehicles with Locking Wheel Bolts
6A To be used for the following:
To Replace 3 Front Studs 0.9 To Replace 5 Front Studs 1.2 To Replace 6 Front Studs 1.7 To Replace 8 Front Studs 1.9 To Replace All Front Studs 2.2
To Replace 3 Rear Studs 0.8 To Replace 5 Rear Studs 1.0 To Replace 6 Rear Studs 1.4 To Replace 8 Rear Studs 1.6 To Replace All Rear Studs 1.8
Time allowance includes 0.1 hour for Dealer administrative detail associated with this campaign. Parts credit should be Dealer net plus 30% to cover parts handling.
SERVICE PROCEDURE:
- Visually inspect all studs and nuts for damage. Wheels with no broken studs or missing nuts should be re-torqued to 136 N.m (100 lb. ft.).
- Wheels with one (1) broken/damaged stud or missing nut should have the stud or nut replaced. The stud and nut on either side of the broken/damaged stud or missing nut should also be replaced (Refer to Front Wheel Bolt Replacement or Rear Wheel Bolt Replacement section in this bulletin as required).
- If more than one (1) stud is broken/damaged or wheel lug nuts are missing, all studs and nuts on the involved wheel are to be replaced. All nuts should be torqued to 136 N.m (100 lb. ft.).
- Wheels should be inspected for damage and replaced if necessary.
- Install Campaign Identification Label.
FRONT WHEEL BOLT REPLACEMENT
NOTE: A 36 mm wheel bolt will be used for front replacement service only. Rear service replacement will use the current 43 mm production bolt.
Remove or Disconnect
1. Raise vehicle.
2. Remove wheel and tire assembly.
3. Remove brake caliper and bracket assembly, hang from vehicle. Do not allow to hang by brake hose.
4. Remove brake rotor.
5. Wheel bolt must be 10 - 12 mm shorter than original (43 mm) length for removal. Cut bolt as necessary and rotate to six o'clock position.
6. Using tool J-6627-A or equivalent, extract bolt from hub (See Illustration).
7. Clean wheel hub flange and rotor of any corrosion, metal chips or foreign material.
Installation
1. Install shorter (P/N 9590474 - 36 mm) replacement bolt in wheel hub.
2. Add enough washers (See Illustration) to draw bolt into hub.
3. Install wheel nut (flat side to washers).
4. Tighten wheel nut until wheel bolt is fully seated against hub flange.
NOTE: MAKE SURE WHEEL BOLT IS FULLY SEATED AGAINST HUB FLANGE.
5. Back off wheel nut and remove washers.
6. Install brake rotor.
7. Install brake caliper and bracket assembly, torque bolts to 200 N.m (148 lb. ft.).
8. Install wheel and tire assembly.
9. Lower vehicle.
10. Tighten wheel nuts to 140 N.m (100 lb. ft.)
REAR WHEEL BOLT REPLACEMENT
1. Raise vehicle.
2. Remove wheel and tire assembly.
3. Remove brake hose bracket.
4. Remove brake caliper, hang from vehicle. Do not allow to hang by brake hose. Tool J-36581 allows easier access for removal as well as installation of caliper bolts.
5. Remove brake rotor.
6. Using tool J-6627-A or equivalent, extract bolt from hub (See Illustration).
7. Clean wheel hub flange and rotor of any corrosion, metal chips or foreign material.
Installation
1. Replacement bolt (P/N 9590476 - 43 mm) in wheel hub.
2. Add enough washers (See Illustration) to draw bolt into hub.
3. Install wheel nut (flat side to washers).
4. Tighten wheel nut until wheel bolt is fully seated against hub flange.
NOTE: MAKE SURE WHEEL BOLT IS FULLY SEATED AGAINST HUB FLANGE.
5. Back off wheel nut and remove washers.
6. Install brake rotor.
7. Install brake caliper and bracket assembly, torque bolts to 123 N.m (91 lb. ft.).
8. Install brake hose bracket and torque bolt to 25 N.m (18 lb. ft.).
9. Install wheel and tire assembly.
10. Lower vehicle.
11. Tighten wheel nuts to 140 N.m (100 lb. ft.)
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:
This notice is sent to you in accordance with the requirements of the Canada Motor Vehicle Safety Act.
General Motors of Canada has determined that a defect which relates to motor vehicle safety may exist in certain 1988 Pontiac Grand Prix Model vehicles. The vehicles could have been assembled with wheellug nuts not installed to specified torque. This condition could allow the lug nuts to loosen and/or come off the wheel studs. If this condition went unnoticed, it could eventually result in the wheel separating from the vehicle. Separation of a wheel from the vehicle could cause loss of vehicle control and a vehicle crash could occur.
To prevent the possibility of this condition occurring, your Dealer will inspect your vehicle to assure proper wheel nut torque. If lug nuts are loose or missing, new lug nuts and wheel studs will be installed. This service will be performed for you at no charge.
Please contact your GM Dealer as soon as possible to arrange a service date. Instructions for performing this inspection/service have been sent to your Dealer. Parts, if required, are available. The labour time necessary to perform the inspection service is approximately fifteen (15) minutes, but additional time will be required if new wheel nuts and studs need to be installed. Please ask your Dealer if you wish to know how much additional time will be needed to schedule and process your vehicle.
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.
We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.
Service Department General Motors of Canada Limited
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.
