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CAMPAIGN: AUTO. TRANSMISSION FLUID CONTAINMENT

SUBJECT: AUTOMATIC TRANSMISSION FLUID CONTAINMENT

MODELS: 1988-90 C/K TRUCKS AND RN SUBURBAN

CAMPAIGN UPDATES AND REPLACES GMC CAMPAIGN NUMBER 90-C-26, ISSUED JANUARY 1992, TO INCLUDE 1988-90 R/V SUBURBANS. DESTROY ALL COPIES OF 90-C-26.

THIS CAMPAIGN HAS BEEN REVISED TO INCLUDE THE ADDITION OF R/V SUBURBANS TO THE POPULATION OF AFFECTED VEHICLES.

Product improvements were made on all 1991 C/ K Trucks and R/V Suburbans equipped with automatic transmissions to help in maintaining the proper transmission fluid level. Transmission fluid level is very important to transmission life and performance; therefore, GMC Truck will make these improvements on 1988-1990 C/K Trucks and R/V Suburbans.

Also, it has come to our attention that some owners are pulling trailers heavier than the vehicle is equipped to pull or loading vehicles with loads greater than that specified for the vehicle as it is equipped. These conditions can result in abnormal pressure build-up in the transmission and the possibility of transmission fluid coming out the filler tube onto hot engine parts.

The possibility of a transmission fluid fire is remote. However, we wanted our owners to have the benefits of the improvements which address this concern, and the maintenance of a proper transmission fluid level.

These improvements consist of (1) revising the transmission fluid level indicator (dipstick) markings so they can be more easily understood, (2) adding a seal at the fill tube inlet end to help prevent fluid from coming out of the fill tube, and (3) revising the fluid level checking procedure in the owner's manual to provide for a "cold" fluid level check. (Note: A "hot" check must follow when fluid is added during a cold check).

To help prevent conditions that could cause transmission pressure build-up and the possibility of transmission fluid coming out of the fill tube, General Motors is providing, to owners, a new dipstick with a lock-seal top and new owner manual instructions and graphics for checking the automatic transmission fluid level.

VEHICLES INVOLVED

Involved are 1988-1990 C/K Trucks and R/V Suburbans with a 4L60 (RPO MD8) or 3L80 (RPO M40) automatic transmissions.

Year Models From Through ---- ------ ---- ------- 1988-90 C/K with 4L60 SOP EOP or 3L80 1988-90 R/V Suburban with SOP EOP 4L60 or 3L80

The specific vehicles involved in this campaign have been identified by Vehicle Identification Number Computer Listings. These listings are furnished to all involved dealers with the campaign bulletin. Dealers should confirm vehicle eligibility through VISS (Vehicle Information Service System) prior to beginning campaign repairs.

DEALER CAMPAIGN RESPONSIBILITY

Since a new dipstick can be installed easily, a new dipstick along with installation instructions will be sent directly to owners of record. Owners may install the dipstick or they may ask a dealer to complete this service. Also, an owner's manual supplement will be sent to owners along with the dipstick and installation instructions.

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. Dealers are to correct all affected vehicles in new and used vehicle stock prior to their sale.

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 ensure the campaign correction has been made before reselling or releasing the vehicle.

OWNER NOTIFICATION

Owners will be notified of this campaign on their vehicles by GMC Truck Division (see copy of owner letter included with this bulletin). A listing of owner names and addresses will NOT be furnished to the involved dealers.

SERVICE PROCEDURE

1. Remove old dipstick.

2. Install new lock-seal dipstick.

PARTS INFORMATION

A new lock-seal fluid level indicator (dipstick), installation instructions and instructions for checking the transmission fluid level will be mailed to owners of record by GMC Truck on a no charge basis.

If additional transmission fluid level indicators are required, they should be obtained from General Motors Service Parts Operation (GMSPO). To ensure that these parts are obtained as soon as possible, they should be ordered from GMSPO on a C.I.O. order with no special instruction code but order under an advise code (2).

Part Number Description Quantity ----------- ----------- -------- 15687192 Indicator, Trans. Fluid 1 Level, MD8 15659781 Indicator, Trans. Fluid Level, 1 M40

WARRANTY INFORMATION

Dealers should submit a warranty claim on each vehicle completed under this campaign.

Labor Operation *Time Parts Trouble Number Description Allowance Allowance Code ------ ----------- --------- --------- ---- V7220 Install Transmission 0.2 Hr. $0.33 96 Fluid Level Indicator (Dipstick)

* For dealer to receive Administrative Time Allowance associated with this campaign, add 0. 1 hour to the Labor Operation Time Allowance.

** The $0.33 amount identified in the "Parts Allowance" column above represents 30% of dealer net for parts that were furnished by GMC Truck Division. This amount is to be placed in the Net Item Amount column of the claim and Type Code "M." This allowance does not apply if it is necessary to order additional parts through GMSPO.

CAMPAIGN IDENTIFICATION LABEL

No Campaign Identification Label is required for this campaign.

ADMINISTRATIVE PROCEDURE

Procedures covering this campaign are outlined in Section V of your dealership's "GMC Truck Warranty Claims Processing Manual" #P9119.

Keep This Sheet In Owner's Manual

TOWING WITH AN OVERDRIVE EQUIPPED AUTOMATIC TRANSMISSION

The drive range should be used for towing a trailer, carrying a heavy load, driving on steep hills, or off-road. Select the drive D position or a lower range as required under any of these conditions. The overdrive range should NOT be used under any of these conditions. Operating in the D position under any of these conditions will minimize heat build up and extend the life of your

Dear GMC Truck Owner:

Product improvements were made on all 1991 Sierras and Suburbans equipped with automatic transmissions to help in maintaining the proper transmission fluid level. Transmission fluid level is very important to transmission life and performance; therefore, GMC Truck will make these improvements on 1988-90 C/K Sierras and R/V Suburbans.

Operating your Sierra or Suburban with an overfilled transmission, pulling loads heavier than the vehicle is equipped to pull, or otherwise overloading the vehicle beyond specifications can result in abnormal pressure build-up in the transmission. If abnormal pressure does build up in the transmission it is possible for transmission fluid to come out the filler tube onto hot engine parts.

The possibility of a transmission fluid fire is remote. However, we wanted our owners to have the benefits of the improvements which address this concern, and the maintenance of a proper transmission fluid level.

These improvements consist of (1) revising the transmission fluid level indicator (dipstick) markings so they can be more easily understood, (2) adding a seal at the fill tube inlet end to help prevent fluid from coming out of the fill tube, and (3) revising the fluid level checking procedure in the owner's manual to provide for a "cold" fluid level check. (Note: A "hot" check must follow when fluid is added during a cold check.)

This product improvement applies to BOTH 3-speed automatic transmissions and 4-speed overdrive automatic transmissions.

Because a new dipstick can be installed easily, for your convenience we have included a new dipstick and installation instructions with this letter. The dipstick installation instructions are on the reverse side of this letter. However, if you desire, your GMC Truck dealer will install the dipstick for you at no charge.

You will find an owner's manual supplement pertaining to automatic transmission fluid with this letter. Peel the protective tape off the pre-gummed area of the owner's manual supplement and place it in the Automatic Transmission Fluid section of your owner's manual.

Please review the updated information on towing with an overdrive equipped automatic transmission and keep it in your owner's manual.

The enclosed postage paid owner reply card identifies your vehicle. Please complete the card to indicate that the campaign repair has been completed and return the card to us. However, if you have sold or traded your vehicle, please furnish us the complete name and address of the person you sold or traded your vehicle to and return the card to us.

We appreciate your cooperation in this matter. We have taken this action in the interest of your continued satisfaction with our product.

GMC TRUCK DIVISION GENERAL MOTORS CORPORATION


Object Number: 87438  Size: MF


Object Number: 94056  Size: MF


Object Number: 94601  Size: MF

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.