No Park with Engine Running

THIS BULLETIN CANCELS AND REPLACES BULLETIN 93-C-52A ISSUED NOVEMBER 1994. ALL COPIES OF 93-C-52A SHOULD BE DESTROYED.

Several different length attaching bolts are used on the 4L60E valve body. It is extremely critical that the correct length bolt is installed in each location. If this procedure is not strictly followed, a binding or "tie up" condition can occur when engaging forward or reverse.

In addition, "Inspection Procedure", Item 2, regarding identification has been revised. The "calendar year" may not be shown on the transmission identification. ALWAYS confirm vehicle eligibility through GMVIS prior to beginning campaign repairs.

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.

General Motors has determined that a defect, which relates to motor vehicle safety, exists in CERTAIN 1993 Chevrolet and GMC 4-wheel drive T model trucks equipped with 4L60-E automatic transmissions. These vehicles may develop significant wear on the low and reverse clutch, which may prevent the park pawl from engaging. This could allow a "no park" condition to occur while the engine is running. Unintentional movement of the vehicle could result in injury to persons in the path of the vehicle. If the ignition is turned off, however, the "no park" condition will not occur.

To prevent the possibility of this condition occurring, dealers are to:

1. Check the transmission fluid for contamination which will indicate if the low and reverse has had excessive wear. If the transmission shows excessive wear, the transmission will be replaced.
2. Remove the right side brace from transmission to transfer case.
3. Modify the transmission case hydraulic oil circuit to prevent the low and reverse piston from being applied in the park (P) range with the engine running if the transmission was produced prior to January 4, 1993.

Involved are 1993 Chevrolet and GMC T Trucks built within the following VIN breakpoints:

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 GMVIS prior to beginning campaign repairs.

All unsold new 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.

When 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.

Owners of vehicles recently sold from your new vehicle inventory are to be contacted by the dealer and arrangements made to make the required correction according to instructions contained in this bulletin.

Owners will be notified of this campaign on their vehicles by General Motors (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.

Inspection Procedure

1. Check transmission fluid for burned fluid and/or contamination. If fluid shows any contamination or that the transmission has been subject to excessive wear, then the transmission should be replaced with a SRTA.

Important: Do not re-install transfer case brace (Figure 1, Item 2).

2. NOTE: Any marginal condition of fluid condition should result in a SRTA installation. Damage to transmission has already occurred.

1.1.	When SRTA installation is required, follow transmission removal and installation procedure in appropriate on-vehicle service manual. Flushing transmission fluid cooler is part of SRTA installation procedures.

1.2.	If SRTA transmission is installed, install Campaign Identification Label when installation is complete. No further action will be required.

3. If fluid is not contaminated, raise vehicle on hoist and locate transmission identification as shown in Figure 2.
4. If the vehicle is determined to be eligible through the use of the GMVIS and the transmission Julian Date is 004 through 020, remove right side brace from transmission to transfer case as seen in Figure 1. Bolt (Figure 1, Item 3) must be replaced. There is no need to replace bolt which originally attached brace to transfer case (Figure 1, Item 1).

After removal of brace is complete, install Campaign Identification Label. No further action is required for these vehicles.

If the vehicle is determined to be eligible through the use of GMVIS and the transmission Julian Date is anything other than 004 through 020, right side brace from transmission to transfer case must be removed as in Step 3a above. In addition, valve body must be removed as described in the on-vehicle section of the applicable service manual. The Transmission Modification Procedure in this bulletin must then be performed.

Transmission Modification Procedure

1. Remove transmission valve body and store in a clean, safe place away from under body of truck. Refer to appropriate 1993 on-vehicle service manual for correct details of this procedure.

NOTE: IT IS EXTREMELY CRITICAL THAT THE CORRECT LENGTH BOLT IS REINSTALLED IN EACH LOCATION. PLEASE MAKE A NOTE AS TO THE LOCATION OF EACH INDIVIDUAL BOLT.

2. Hang wire harness out of way and clean case with solvent (Figure 3).
3. Thoroughly dry case with shop air (Figure 4).
4. Attach tool J41350 to case with bushing and lettering facing floor as shown in Figures 5 and 6.
5. Use bolts provided with tool and install all bolts finger tight prior to tightening to eliminate possible bolt misalignment (Figure 6).
6. Torque all bolts to 5 N·m(44 lb in) (Figure 7).

Notice: If valve body bolts are used with tool they will cause damage to case due to length differences. Use bolt supplied with special tool J41350.

7. Drill out case using drill bit provided in tool kit J41350. Apply cutting fluid to drill. The plate from tool kit J41350 has a drill guide bushing in the center. Drill bit should be placed in drill guide bushing when drilling out case. Depth of drill must go until shoulder stop of the drill bit meets the drill bushing to guarantee proper depth (Figure 8) and to open the oil channel.

Notice: Do not drill case with valve body or other related hardware directly below.

8. Remove tool J41350 from case (Figure 9).
9. Clean case with solvent (Figure 10).
10. Thoroughly dry case with shop air (Figure 11). Repeat if necessary.
11. Using stone provided with tool kit J41350, stone surface of case where hole has been drilled to remove any burrs. Inspect for loose burrs in hole and channel that was drilled (Figure 12).
12. Clean case with solvent (Figure 13).
13. Thoroughly dry case with shop air (Figure 14). Repeat stone cleaning procedure until transmission cavity is free of all burrs and metal debris.
14. Install new manual valve (supplied in transmission fix kit) in valve body (Figure 15).
15. Remove all filters from old spacer plate, clean them with solvent and put them on new spacer plate provided in transmission fix kit.
16. Install valve body using new valve body gaskets and new spacer plate provided in transmission fix kit (be sure filters have been installed on spacer plate). Old valve body gaskets and spacer plates are not to be reused.

NOTE: PLEASE REFER TO THE 1993 UNIT REPAIR MANUAL (X9337), PAGE 7A-14B-54, FIGURE 112, FOR THE PROPER VALVE BODY BOLT LOCATIONS.

17. Install new transmission oil filter and install transmission oil pan using new transmission oil pan gasket.

17.1.

Refill transmission with 4 quarts of automatic transmission fluid (Dexron IIE or Dexron III).

17.2.

Start unit and engage all gears. Recheck transmission fluid level and adjust level as required. Inspect for any fluid leaks and correct before returning unit to customer.

18. Install new PROM (MEM-CAL) as described in On-Vehicle section of service manual.
19. Apply "Campaign Identification Label."

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).

Each dealer was shipped special tool kit, J 41350, for use in this campaign during the week of October 17, 1994. This kit, furnished at no charge, was labeled "CAMPAIGN MATERIAL - ATTENTION SERVICE MANAGER".

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

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

** The "Parts Allowance" should be the sum total of the current GMSPO dealer net price plus 30% of all parts required for the repair including transmission fluid for labor operations V8951 and V8952.

***Chevrolet use SK-00 for CC-FC.

Dealers will automatically receive the correct labor and material allowance based on the labor operation performed.

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.

Procedures covering this campaign are outlined in Section V of your dealership's "Truck Warranty Claims Processing Manual" #P9119 Rev 2/94.

Dear General Motors 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 1993 Chevrolet and GMC 4-wheel drive T model trucks equipped with 4L60-E automatic transmissions. These vehicles may develop significant wear on the low and reverse clutch, which may prevent the park pawl from engaging. This could allow a "no park" condition to occur while the engine is running. Unintentional movement of the vehicle could result in injury to persons in the path of the vehicle. If the ignition is turned off, however, the "no park" condition will not occur.

To prevent the possibility of this condition occurring, dealers are to:

1. Check the transmission fluid for contamination which will indicate if the low and reverse has had excessive wear. If the transmission shows excessive wear, the transmission will be replaced.
2. Remove the right side brace from transmission to transfer case.
3. Modify the transmission case hydraulic oil circuit to prevent the low and reverse piston from being applied in the park (P) range with the engine running if the transmission was produced prior to January 4, 1993.

Instructions for performing this service have been sent to your GM dealer. Please contact your dealer to arrange a service date. The labor time necessary to perform this correction ranges from approximately 30 minutes to 3 hours, depending on the repairs required. Please ask your dealer how much additional time will be needed to process your vehicle.

Your GM 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 GM 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 GM, 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 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.

General Motors Corporation

93C52B

Enclosure