CAMPAIGN:INFORMATION DELCOTRON GENERATOR REGULATOR. GMC Truck GMC C Pickup

MODELS: 1983-84 S/T 15 JIMMY'S WITH C60 AIR CONDITIONING AND C49 REAR WINDOW DEFOGGER 1983-84 C/K 15-25 SUBURBANS WITH C36 REAR AUXILARY HEATER AND C49 REAR WINDOW DEFOGGER

General Motors has determined that some 1983-84 S/T 15 Jimmy's and C/K 15-25 Suburbans, equipped with the 78 Amp Delcotron gene4rator may be subject to voltage regulator fialure under certain conditions of termperature load, and engine/generator speed. The resulting failure of the voltage regulator can cause high system voltage and lead to loss of generator output.

To prevent the possibility of this inconvenience occurring, it will be necessary to replace the voltage regulator with one that is not affected by temperature load, and engine/generator speed conditions.

VEHICLES INVOLVED

Involved are certain 1983-84 S/T 15 Jimmy's equipped with C60 air conditioning and C49 rear window defogger. Vehicles with this option combination have the 78 Amp Delcotron genertor. These vehicles were built within the following VIN breakpoints:

Year Plant From Through ---- ----- ---- -------

1983 Pontiac D0500002 D0524473 Shreveport D8505488 D8515152

1984 Pontiac E0500019 E0519059 Shreveport E8500005 E8521022

Also involved are certain 1983-84 C/K 15-25 Suburbans equipped with C36 rear auxiliary heater and C49 rear window defogger. Vehicles with this option combination have the 78 Amp Delcotron generator. These vehicles were built within the following VIN breakpoints.

Year Plant From Through ---- ----- ---- -------

1983 Flint DF501779 DF530565 1984 Flint EF500651 EF519963

The specific vehicles invoived in this campaign have been identified by Vehicle Identification Number Computer Listings. These listings are furnished to all involved dealers with the campaign bulletin.

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.

If no owner's name and address were available to GMC Truck at the time of campaign initiation, the dealer will determine the owner's name and address from the dealership sales records. Please provide this information directly on the second copy of the listing next to the applicable VIN, so that our records may be updated and the appropriate notification mailed to the owner. This second copy should then be submitted to the address listed below in the previously supplied yellow campaign envelopes.

GMC Truck General Motors Corporation 101 Union Street Plymouth, Michigan 48170

OWNER NOTIFICATION

Owners will be notified of this campaign on their vehicles by GMC Truck (see copy of Owner Letter included with this bulletin). A listing of owner names and addresses has been furnished to the involved dealers to enable dealers to follow up with owners involved in the campaign. This listing may contain owner names and addresses obtained from state motor vehicle registration records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states. Accordingly, you are urged to limit the use of this listing to this campaign.

SERVICE PROCEDURE

The voltage regulator is mounted inside the generator and is attached to the slip ring end frame. Replacement of the voltage regulator will involve removal and partial disassembly of the generator. The procedures for generator removal and disassembly are outlined in the appropriate service manual.

Reference Service Manuals Pages ------------------------- ----- X-8332 83 Light Duty Trucks 6D-26-27 X-8432 84 Light Duty Trucks 6D-26-27 X-8329 83 S-Truck 6D-24-27 X-8429 84 S-Truck 6D-24-27

Instructions are also included with the replacement regulator.

PARTS INFORMATION

Parts are to be obtained from the Warehousing and Distribution Division of General Motors (WDDGM). To ensure that these parts will be obtained as soon as possible, they should be ordered from WDDGM on C.I.O. order with no special instruction code, but order on an advise code (2).

Part Number Quantity Description ----------- -------- ------------ 1116409 1 Voltage Regulator

WARRANTY INFORMATION

Dealers should submit an accurately filled out Warranty Repair Order on each vehicle completed under this campaign.

S/T 15 Jimmy's with L-4 Engine

Labor Operation *Time Trouble Number Description Allowance Code ------ ----------- --------- ----

V2210 Remove and Replace 0.7 hr. 96 Voltage Regulator. Includes R & R Generator

S/T 15 Jimmy's with V-6 Engine Labor Operation *time Trouble Number Description Allowance Code ------ ----------- --------- ----

V2211 Remove and Replace 0.5 hr. 96 Voltage Regulator. Includes R & R Generator

C/K 15-25 Suburbans with V-8 Engine (Exc. Diesel) Labor Operation * Time Trouble Number Description Allowance Code ------ ----------- ---------- ----

V2212 Remove and Replace 0.6 Hr. 96 Voltage Regulator. Includes R & R Generator

C/K 15-25 Suburbans with Diesel Engine Labor Operation *Time Trouble Number Description Allowance Code ------ ----------- --------- ----

V2213 Remove and Replace 0.5 Hr. 96 Voltage Regulator. Includes R & R Generator

*For dealer to receive Administration Time Allow ance associated with this campaign, add 0.1 Hr. to the Labor Operation Time Allowance.

CAMPAIGN IDENTIFICATION LABEL

Each vehicle modified in accordance with the instructions outlined in this product campaign bulletin will require a "Campaign Identification Label". Each label provides a space to include the five (5) digit Dealer Code of the dealer performing the campaign service. This information may be inserted with a typewriter or ballpoint pen.

Each "Campaign Identification Label" is to be located on the radiator core support in an area which will be visible when the vehicle is brought in for periodic servicing by the owner.

Apply "Campaign Identification Label" only on a clean dry surface.

ADMINISTRATIVE PROCEDURE

Procedures covering this campaign are outlined in Section V of your dealership's "GMC Truck Claims Processing Manual" issued April, 1983.

Dear GMC Truck Owner:

General Motors has determined that some 1983-84 S/T 15 Jimmy's and C/K 15-25 Suburbans equipped with the 78 Amp Delcotron generator may be subject to voltage regulator failure under certain conditions of temperature, load, and engine/generator speed. The resulting failure of the voltage regulator can cause high system voltage and lead to loss of generator output.

To prevent the possibility of this condition occurring on your vehicle, please contact your GMC dealer on or after July 9, 9184 to arrange a service date. Your dealer will install a new voltage regulator on your vehicle. This service will be performed for you at no charge.

Instructions for making this correction have been sent to your GMC dealer. The labor time required to install the new voltage regulator is approximately 40 minutes. Please allow additional time for the dealer to process your vehicle.

The enclosed owner reply car identifies your vehicle. Presentation of this card to your dealer will assist him in making the correction to your vehicle in the shortest possible time. If you have sold or traded your vehicle, please let us know by completing the postage paid owner reply card and returning it to us.

We are sorry to cause you this inconvenience, however, we have taken this action in the interest of your safety and 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.