SPECIAL POLICY: COLD IDLE SPEED REDUCTION
MODELS: 1985 M VANS WITH 4.3L ENGINE AND AUTOMATIC TRANSMISSION
Some customers may experience a condition immediately after cold vehicle startup where, by applying the brake pedal, they are unable to completely stop the rear wheels from turning on icy surfaces.
Variables such as rear axle ratios and higher engine rpm while the vehicle is in the cold idle mode can result in inereased torque to the rear wheels. These variables, in conjunction with a lightly loaded rear axle, can increase the pedal effort required to stop the rear wheels from spinning on ice when the vehicle is placed in gear. This condition can be effectively addressed by using the service procedure to reduce the cold idle speed of the engine.
SPECIAL POLICY ADJUSTMENT
Should this condition occur, GMC Truck Division will repair involved vehicles at no charge for a period of five years, regardless of mileage from the date the vehicle was originally placed in service.
This "SPECIAL POLICY ADJUSTMENT BULLETIN" should be filed in the three ring binder furnished each dealer by General Motors.
OWNER NOTIFICATION
Owners of vehicles involved in this SPECIAL POLICY ADJUSTMENT will be notified by GMC Truck (see copy of owner letter included with this Bulletin).
SERVICE PROCEDURE - 1985 MODEL 4.3L CARBURETED ENGINE ----------------------------------------------------- Reduce cold idle speed to 1600 rpm.
1. Remove dash extension.
2. Remove engine cover.
3. Install tachometer. The tachometer (tach) terminal is next to the engine control switch (bat) connector on the distributor cap (Reference Figure No. 1).
NOTICE: The tachometer terminal must never be allowed to touch ground, because damage to the module inside the distributor and/or ignition can result sult.
4. Reduce cold idle speed to 1600 rpm by adjusting the fast idle screw. Refer to tune up label for procedure.
5. Remove tachometer and reinstall engine cover and dash extension.
6. On a clean dry surface, next to the existing tune up label located on the fan shroud, place label P/N 10066488.
PARTS INFORMATION
Labels to show fast idle speed specification change have been shipped directly to all dealers who originally ordered 1985 M vans. If additional labels are required please call: Adistra Corporation, (313) 425-2600, Extension 396.
PART NUMBER DESCRIPTION QUANTITY ----------- ----------- -------- 10066488 Label 1
The label is not to be ordered from General Motors Service Parts Operation (GMSPO).
WARRANTY INFORMATION
Dealers should submit a warranty claim on each vehicle completed.
LABOR OPERATION TIME *NET NUMBER DESCRIPTION ALLOWANCE AMOUNT --------- ----------- --------- ------ T7395 Adjust idle .6 .30 speed and install label
T7425 Reimburse- ment for previous repairs
* The 30 cents identified in the net amount column represents 30% of dealer net when parts are furnished no charge by GMC Truck Division.
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Dear GMC Truck Owner:
This letter has been sent to inform you of the following special policy that applies to your vehicle.
REASON FOR THIS SPECIAL POLICY
Some owners of 1985 GMC Safari vans equipped with 4.3L V-6 engines and automatic transmissions may experience a condition immediately after cold vehicle startup where, by applying the brake pedal, they are unable to completely stop the rear wheels from turning on icy surfaces.
Variables such as rear axle ratios and higher engine rpm while the vehicle is in the cold idle mode can result in increased torque to the rear wheels. These variables, in conjunction with a lightly loaded rear axle, can increase the pedal effort required to stop the rear wheels from spinning on ice when the vehicle is placed in gear. This condition can be effectively addressed by reducing the cold idle speed of the engine.
SPECIAL POLICY COVERAGE
Because this condition could occur beyond the warranty period and is affected by climatic conditions in various locations in the United States, we are writing this lefter to advise you that GMC Truck Division will repair your vehicle at no charge for a period of five years, regardless of mileage from the date the vehicle was originally placed in service. This repair will consist of reducing the cold idle speed of the engine.
WHAT YOU SHOULD DO
In the event your Safari van encounters a condition as outlined above, contact your GMC Truck dealer. Instructions have been furnished to GMC Truck dealers for repairing this condition and handling of this special policy.
If you have previously encountered this condition and paid for all or part of the repair, you should contact your GMC Truck dealer who will advise you regarding reimbursement. It will be necessary to present paid receipts or invoices to verify any expenditures for such repairs, so you should have them available when you contact your dealer.
We suggest you retain this letter with your Owner's Manual, Maintenance Guide, and Warranty Folder.
GMC Truck Division is taking this action in the interest of your continued satisfaction with our products.
GMC TRUCK DIVISION GENERAL MOTORS CORPORATION
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.
