CAMPAIGN:TRANSMISSION FLUID LEAK DUE TO IMPROPER CASE WALL

SUBJECT: TRANSMISSION FLUID LEAK DUE TO IMPROPER CASE WALL THICKNESS

MODELS: 1995 C/K & P TRUCKS, G VANS EQUIPPED WITH THE HYDRA-MATIC 4L80-E AUTOMATIC TRANSMISSION (MT1)

THIS BULLETIN CANCELS AND REPLACES BULLETIN 95-C-24C ISSUED JUNE, 1995.

THE WARRANTY INFORMATION HAS BEEN REVISED FOR THE G-VAN (LABOR OPERATION V9553). THE TIME ALLOWANCE IS 2.4 HOURS.

ALL COPIES OF 95-C-24C SHOULD BE DESTROYED.

The National Traffic and Motor Vehicle Safety Act, as amended, provides that each vehicle which is subject to a recall campaign of this type must be adequately repaired within a reasonable time after the owner has tendered it for repair. A failure to adequately repair within 60 days after tender of a vehicle is prima facie evidence of failure to repair within a reasonable time.

If the condition is not adequately repaired within a reasonable time, the owner may be entitled to an identical or reasonably equivalent vehicle at no charge, or to a refund of the purchase price less a reasonable allowance for depreciation.

To avoid having to provide these burdensome solutions, every effort must be made to promptly schedule appointments with owners and to repair their vehicles as soon as possible. As you will see in reading the attached copy of the letter which is being sent to owners, the owner is being instructed to contact the GMC Truck Division Consumer Relations Office if the dealer does not remedy the condition within five days of the mutually agreed upon service date. If the condition is not remedied within a reasonable time, they are instructed how to contact the National Highway Traffic Safety Administration.

DEFECT INVOLVED

General Motors has determined that a defect, which relates to motor vehicle safety, exists in CERTAIN 1995 GMC Truck C/K & P Trucks, and G Vans equipped with the Hydra-Matic 4L80-E automatic transmission (MT1). A condition exists where some of these vehicles may experience an external transmission fluid leak at the lube feed passage due to a thin case casting in the cooler boss area. This condition could cause transmission oil to spray onto the exhaust system and start a vehicle fire.

To correct this condition, dealers will inspect the transmission case assembly for the involved case casting. If the transmission assembly is involved, then the transmission will be replaced using the procedure outlined in this bulletin.

VEHICLES INVOLVED

Involved are CERTAIN 1995 GMC Truck C/K & P Trucks, and G Vans, equipped with the Hydra-Matic 4L80-E automatic transmission (MT1) built within the following VIN breakpoints:

Plant Year Model Plant Code From Through --------------------------------------------------------------------------- 1995 C/K Oshawa 1 522506 526071 1995 C/K Pontiac East E 509028 513138 1995 C/K Janesville J 704498 719762 1995 C3500 HD Janesville J 506942 511985 1995 G Flint F 515428 522360 1995 P Detroit 3 501150 501674

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

DEALER CAMPAIGN RESPONSIBILITY

The dealer will need to inspect all 4L80-E Goodwrench transmission assemblies in the parts inventory for suspect 4L80-E transmission assemblies. The dealer will also need to contact customers who purchased a 4L80-E Goodwrench transmission assembly over the counter or dealers who were traded a unit between December 15, 1994 and January 20, 1995.

All unsold vehicles in dealers' possession and subject to this campaign MUST be held and inspected/repaired per the service procedure of this campaign bulletin BEFORE owners take possession of these vehicles.

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.

Owners of vehicles recently sold from your new vehicle inventory with no owner information indicated on the dealer listing, are to be contacted by the dealer, and arrangements made to make the required correction according to the instructions contained in this bulletin. This could be done by mailing to such owners a copy of the owner letter accompanying this bulletin. Campaign follow-up cards should not be used for this purpose, since the owner may not as yet have received the notification letter.

In summary, whenever a vehicle subject to this campaign enters your vehicle inventory, or is in your dealership for service in the future, please take the steps necessary to be sure the campaign correction has been made before selling or releasing the vehicle.

If the name and address of the owner of an involved vehicle was unavailable to GMC Truck Division at the time of campaign initiation, the dealer must 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 Division General Motors Corporation 101 Union Street Plymouth, Michigan 48170

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 has been furnished to the involved dealers to enable dealers to follow up with owners involved in this 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

Suspect Transmission Cases Must Be A Casting Die #4 And Be Within The Case Cast Date Clock Dates And Within The Julian Date As Outlined. If The Die Number Or Dates Are Not Within The Guidelines, The Transmission Is Not Involved And No Further Action Is Required, Go To Step 6.

SCENARIO #1: 1995 vehicles produced with suspect transmission assembly which are in dealer new vehicle inventory or have been sold to a customer.

1. Raise the vehicle on a hoist and locate the transmission casting die number on the left side of the transmission case (see Figure 1).

IF THE CASTING DIE NUMBER IS #4 AND IT IS NOT CIRCLED WITH GREEN INK OR IS BLANK, PROCEED TO STEP 2.

NOTE: ALL OTHER CASTING DIE NUMBERS ARE NOT INVOLVED. If the casting die number is #4 and it is circled with green ink, the case is okay, or if the casting die number is other than #4, proceed to step 6.

2. Locate the case casting date (see Figure 1).

If the case cast date clock on the driver's side of the transmission case is between 494 (49=week of year; 4=year 1994) and 025 (02=week of year; 5=year 1995), proceed to step 3. If not within the guidelines, the transmission is not involved, go to step 6.

3. Locate the transmission Julian date (see Figure 2).

If the Julian date is within the 1994 Julian date 339 through the 1995 Julian date 012, proceed to step 4. If not within the guidelines, the transmission is not involved, go to step 6.

4. Replace the transmission assembly. Use the appropriate 1995 Service Manual, Section 7A17B, for the transmission replacement procedure.

5. The removed transmission assembly must be returned in the original shipping container and using the customary GMSPO process.

IMPORTANT: The Product Feedback form MUST include the VIN, the mileage, and the campaign number. PLEASE HIGHLIGHT THE DIE CASTING NUMBER #4 BY CIRCLING IT WITH A GREASE MARKER, PAINT STICK, OR A PERMANENT INK MARKER. Do not use green.

6. Install Campaign Identification Label.

SCENARIO #2: Any 1991-1995 4L80-E Goodwrench transmission assemblies in Dealer Parts Inventory which were ordered from GMSPO BETWEEN DECEMBER 15,1994 AND JANUARY 20, 1995.

A listing of suspect 4L80-E transmissions purchased from GMSPO is being supplied to the involved dealers with this bulletin.

1. Locate the transmission casting die number on the left side of the transmission case (see Figure 1).

IF THE CASTING DIE NUMBER IS #4 AND IS NOT CIRCLED WITH GREEN INK, OR IS BLANK, PROCEED TO STEP 2.

NOTE: ALL OTHER CASTING DIE NUMBERS ARE NOT INVOLVED. If the casting die number is #4 and it is circled with green ink, or if the casting die number is other than #4, NO FURTHER ACTION IS REQUIRED. The green ink circle indicates that the cast has been inspected and is okay.

2. Locate the case casting date (see Figure 1).

If the cast casting date clock on the driver's side of the transmission case is between 494 (49=week of year; 4=year 1994) and 025 (02=week of year; 5=year 1995), proceed to step 3. If the date is not within the guidelines, the transmission is not involved.

3. Locate the transmission Julian date.

If the Julian date is within the 1994 Julian date 339 through the 1995 Julian date 013, (Figure 2), proceed to step 4. If not within the Julian dates, the transmission is not involved.

4. GMSPO return process.

The transmission assembly must be returned in the original shipping container and with the appropriate information indicating that the transmission assembly is involved in this recall campaign. PLEASE HIGHLIGHT THE DIE CASTING NUMBER #4 BY CIRCLING IT WITH A GREASE MARKER, PAINT STICK OR A PERMANENT INK MARKER. Do not use green.

SCENERIO #3: Any 1991-1995 4L80-E Goodwrench transmission assemblies ORDERED FROM GMSPO BETWEEN DECEMBER 15,1994 AND JANUARY 20,1995 and installed into a customer vehicle by the dealership or sold over the counter or dealer traded.

VIN numbers of vehicles that have had a 4L80-E transmission replaced by the dealer under warranty have been included with the campaign listing.

1. The dealership will need to determine:

a. which customer vehicles they installed the suspect 4L80-E Goodwrench transmission assembly into

b. which customers purchased a suspect 4L80-E Goodwrench transmission assembly

c. which dealers they traded a suspect 4L80-E Goodwrench transmission assembly over the counter with.

2. The dealership will need to contact these customers to arrange an inspection of the transmission case assembly per the instructions in Scenario #1.

PARTS INFORMATION

Parts are to be obtained from General Motors Service Parts Operation (GMSPO). To ensure that these parts will be 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).

IMPORTANT: Transmission cores must be returned to GMSPO as the new transmission is installed. The original transmission assembly must be placed in the replacement transmission container and returned through the customary GMSPO process.

Engine Part Number Description Vehicle Model 4L80E Model Disp/RPO Quantity ----------------------------------------------------------------------------- 24201746 Transmission P Truck 5ABP 4.3L/LB4 1 24201748 Transmission G Van 5ADP 4.3L/LB4 1 24201752 Transmission G Van 5ALP 6.5L/L57 1 24201753 Transmission C Truck 5BAP 5.7L/L05 1 24201754 Transmission K Truck 5BJP 5.7L/L05 1 24201755 Transmission P Truck 5BMP 5.7L/L05 1 24201756 Transmission C Truck 5BNP 5.7L/L05 1 24201758 Transmission C Truck 5CSP 5.7L/L05 1 24201759 Transmission C Truck 5CTP 6.5L/L65 1 24201760 Transmission C Truck 5CWP 7.4L/L19 1 24201761 Transmission C Truck 5CXP 7.4L/L19 1 24201762 Transmission K Truck 5DLP 7.4L/L19 1 24201763 Transmission P Truck 5DNP 7.4L/L19 1 24201764 Transmission P Truck 5DPP 7.4L/L19 1 24201765 Transmission C Truck 5DRP 7.4L/L19 1 24201767 Transmission P Tk & G Van 5LAP 6.5L/L65/L57 1 24201768 Transmission C Truck 5LBP 6.5L/L65 1 24201769 Transmission K Truck 5LFP 6.5L/L65/L56 1 24201770 Transmission P Truck 5LHP 6.5L/L65/L57 1 24201771 Transmission C Truck 5LLP 6.5L/L65 1 24201772 Transmission P Truck 5LUP 6.5L/L65 1 24201773 Transmission C Truck 5LYP 6.5L/L56 1 24201774 Transmission P Tk & G Van 5MBP 5.7L/L05 1 24201866 Transmission G Van 5MCP 5.7L/L05 1 24201780 Transmission P Tk & G Van 5TWP 7.4L/L19 1 24201781 Transmission G Van 5TXP 7.4L/L19 1 12346143 Transmission --- --- --- 8 Qts. Fluid 15629093 Gasket, T-Case --- --- --- 1 Adapter 8681168 Seal, T-Case --- --- --- 1 Adapter

WARRANTY INFORMATION

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

Labor Operation *Time Cause Net Number Description Allowance Code Amount ----------------------------------------------------------------------------- V9549 All 1995 Vehicles - 0.2 96 Inspection Only V9550 1995 C Truck (non 3500 HD) - 2.5 96 ** Inspect & Replace Transmission V9551 1995 C Truck (3500 HD) - 2.6 96 ** Inspect & Replace Transmission V9552 1995 K Truck - 4.2 96 ** Inspect & Replace Transmission V9553 1995 G Van - 2.4 96 ** Inspect & Replace Transmission V9554 1995 P Truck - 2.6 96 ** Inspect & Replace Transmission

THE FOLLOWING "T" LABOR OPERATIONS SHOULD BE USED IN SCENARIO #3 ONLY. SUSPECT GOODWRENCH TRANSMISSIONS WERE INSTALLED IN CUSTOMER VEHICLES AND THE VIN DOES NOT APPEAR IN VISS OR SERVICENET.

T2015 All 1991-1995 Vehicles - Inspection Only Use Applicable Model Labor ** T2016 All 1991-1995 Vehicles - Times As Shown Above Inspect & Replace Transmission

* For dealer to receive Administrative Time Allowance associated with this campaign, add 0.1 hour to the Labor Operation Time Allowance.

** Transmission Fluid is a net item. Submit actual cost for oil plus 40% markup. Enter as Net Item Code M.

CAMPAIGN IDENTIFICATION LABEL

Each vehicle corrected 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 campaign number and five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or ball point 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 Warranty Claims Processing Manual" #P9119 Rev. 2/94.

Dear GMC Truck Owner:

This notice is sent to you in accordance with the requirements of the National Traffic and Motor Vehicle Safety Act.

General Motors has determined that a defect, which relates to motor vehicle safety, exists in certain 1995 GMC Truck and Vans with the Hydra-Matic 4L80-E automatic transmission. A condition exists where some vehicles may have been built with an improperly cast transmission case. This condition can result in a transmission fluid leak onto the exhaust system that may cause a vehicle fire.

To correct this condition, your GMC Truck dealer will inspect the transmission case assembly. The transmission will be replaced for you at no charge if it is one that is a suspect assembly.

Instructions for performing this service have been sent to your GMC Truck dealer. Please contact your dealer to arrange a service date. The labor time necessary to perform this correction will range from approximately 15 minutes to 4 hours, depending on the work required. Please ask your dealer how much additional time will be needed to process your vehicle.

Your GMC Truck dealer is best equipped to provide service to ensure your vehicle is corrected as promptly as possible. However, if you take your vehicle to your dealer on the agreed service date and they do not service this condition on that date or within five days, we recommend you contact GMC Truck Consumer Relations by telephone. Consumer Relations will assist you and your dealer in getting your vehicle corrected. The telephone number of the Consumer Relations office is listed in your Warranty and Owner Assistance Information Manual.

After contacting your dealer and GMC Truck Division, if you are still not satisfied that we have done our best to remedy this condition without charge within a reasonable time, you may wish to write the Administrator, National Highway Traffic Safety Administration, 400 Seventh Street, S.W., Washington, D.C., 20590, or call 800-424-9393 (Washington, D.C. residents use 366-0123).

The enclosed postage paid owner reply card identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction to your vehicle in the shortest possible time. If you have sold or traded your vehicle, please furnish us complete name and address of the person you sold or traded your vehicle to and return the card 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 product.

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.