CAMPAIGN: FOUR SPEED MANUAL TRANSMISSION LOCKS IN REVERSE

Model and Year: 1988 C/K 10-30 SERIES TRUCKS EQUIPPED WITH 4-SPEED MANUAL TRANSMISSION (RPO MM4)

General Motors has determined that the transmission and transmission shift lever on some 1988 Chevrolet C/K 10-30 series trucks equipped with 4-speed manual transmission (RPO MM4) could remain locked in the reverse position, due to the shift lever finger not adequately being retained in the reverse gate.

When the shift lever finger slips out of the reverse gate, the shift lever can be moved very little from this location. It is apparent to a driver that the transmission is in reverse, because the lever is close to the normal reverse location.

To correct this condition, it will be necessary to replace the transmission cover assembly in all involved vehicles.

VEHICLES INVOLVED

Involved are certain 1988 Chevrolet C/K 10-30 series trucks equipped with 4-speed manual transmission (RPO MM4) built within the following VIN breakpoints:

PLANT FROM THROUGH ----- ---- ------- Pontiac East JE100008 JE103314 Fort Wayne JZ100291 JZ102381 Oshawa J1100155 J1111148

Involved vehicles have been identified by Vehicle Identification Number Computer Listings. Computer listings contain the complete Vehicle Identification Number, owner name and address data, and are furnished to the involved dealers with the campaign bulletin. Owner name and address data furnished will enable dealers to follow-up with owners involved in this campaign.

These listings 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 the follow-up necessary to complete this campaign. Any dealer not receiving a computer listing with the campaign bulletin has no involved vehicles currently assigned.

OWNER NOTIFICATION

Owners will be notified of this campaign on their vehicles by Chevrolet Motor Division (see copy of Owner Letter included with this 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 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 correction according to instructions contained in this bulletin.

PARTS INFORMATION

Parts required to complete this campaign are to be obtained from General Motors Service Parts Operations (GMSPO). To ensure that these parts are obtained as soon as possible, they should be ordered on a C.I.O. with no special instruction code, but on an advise code (2).

PART NUMBER DESCRIPTION QUANTITY ------ ----------- -------- 8672020 Transmission Cover Assembly 1 14020854 Gasket - Transfer Case to Adapter 1 15594369 Gasket - Transmission Cover 1 1051855 Dexron II Fluid 1.2 qts 1052271 SAE-80W GL-5 or SAE-80W-90 GL5 Gear Lube 4.2 qts

SERVICE PROCEDURE

Refer to 1988 C/K Service Manual (ST-375-88) Section 4, Propeller Shaft & Axles, and Section 7, Transmission and Clutch for further removal and installation instructions.

4-WHEEL DRIVE EQUIPPED VEHICLES

1. Place transfer case in 4H. 2. Disconnect negative battery cable. 3. Unclip and remove shift lever boot from console. 4. Remove shift lever assembly from transmission. 5. Remove console. 6. Lift and support vehicle. 7. Remove transfer case skid plate if equipped. 8. Drain lubricant from transfer case and transmission. 9. Disconnect transfer case shift control linkage. 10. Disconnect wiring harness and vent hose from transfer case. 11. Disconnect front propshaft at transfer case flange. - Reference mark the relationship of the propshaft at the flange. 12. Remove rear propshaft. 13. Remove transfer case to transmission adapter bolts. 14. Remove transfer case. 15. Disconnect wiring harness from transmission. 16. Remove transmission mount to crossmember nuts. 17. Support and raise transmission with an appropriate jack. 18. Remove crossmember. 19. Remove transmission to clutch housing bolts. 20. Remove transmission and place on a bench. - Before removing cover assembly from transmission ensure that all forward gears are in neutral and reverse is halfway engaged. 21. Remove transmission cover. Clean case of all gasket material. 22. Place new cover assembly halfway in reverse, Figure No. 1, and install new gasket and cover assembly to transmission. Torque bolts 34 Nm (25 lb ft). 23. Reinstall transmission in vehicle. Transmission should be in reverse gear. Torque transmission to clutch housing bolts to 100 Nm (74 lb ft). 24. Reinstall crossmember. Torque mounting bolts to 75 Nm (55 lb ft). 25. Torque transmission mount to crossmember nuts to 47 Nm (35 lb ft). 26. Reconnect wiring harness to transmission. 27. Reinstall transfer case to transmission adapter utilizing a new gasket. Torque bolts to 33 Nm (24 lb ft). 28. Reconnect front propshaft. Torque flange bolts to 100 Nm (74 lb ft). 29. Reconnect vent hose and wiring harness to transfer case. 30. Reconnect transfer case linkage. 31. Reinstall skid plate if previously removed. 32. Refill transfer case with Dexron II Automatic Transmission Fluid P/N 1051855 (approx. 1.2 quarts). 33. Refill transmission with SAE-80W GL-5 or SAE-80W-90 GL5 gear lubricant P/N 1052271 (approx. 4.2 quarts). 34. Lower vehicle. 35. Replace console, shift lever assembly, shift lever boot, etc. 36. Reconnect the battery. 37. Install Campaign Identification Label.

2-WHEEL DRIVE EQUIPPED VEHICLES

1. Disconnect negative battery cable. 2. Unclip and remove shift lever boot from console. 3. Remove shift lever assembly from transmission. 4. Remove console. 5. Raise and support vehicle. 6. Drain lubricant from transmission. 7. Disconnect wiring harness from transmission. 8. Disconnect propshaft from transmission. Loosen hanger bearing and tie shaft away from work area. 9. Remove transmission mount to crossmember nut. 10. Support transmission. 11. Remove transmission bolts at clutch housing. 12. Remove crossmember. 13. Remove transmission and place on a bench. - Before removing cover assembly from transmission ensure that all forward gears are in neutral and reverse is halfway engaged. 14. Remove transmission cover. Clean case of all gasket material. 15. Place new cover assembly halfway in reverse, Figure No. 1; and installnew gasket and cover assembly to transmission. Torque bolts 34 Nm (25 lb ft). 16. Reinstall transmission in vehicle. Transmission should be in reverse ear. Torque transmission to clutch housing bolts to 100 Nm (74 lb ft). 17. Reinstall crossmember. Torque mounting bolts to 75 Nm (55 lb ft). 18. Torque transmission mount to crossmember nut 54 Nm (40 lb ft). 19. Reconnect wiring harness. 20. Reconnect propshaft to yoke. Torque bolts to 20 Nm (15 lb ft). Torque center bearing bracket bolts to 34 Nm (25 lb ft). 21. Fill transmission with SAE-80W GL-5 or SAE-80W-90 GL5 gear lubricant P/N 1052271 (approx. 4.2 quarts). 22. Lower vehicle. 23. Replace console, shift lever assembly, shift lever boot, etc. 24. Reconnect the battery. 25. Install Campaign Identification Label.

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 five 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.

CLAIM INFORMATION

Submit a Product Campaign Claim with the information indicated below: * *** Failed Parts Labor Lab Oth Net Repair Performed PC Part No. Allow FC OP Hrs Hrs Amt

Replace transmission 3 8672020 ** 00 V4130 1.4 0.1 $17.94 cover assembly - "C" Model trucks

Replace transmission 3 8672020 ** 00 V4131 2.1 0.1 $22.36 Cover assembly - "K" model trucks

*Campaign Administrative 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.

***The $17.94 in the "Net Amount" Column represents the cost of gear lubricant, plus 30%, used in conjunction with "V" operation V4130 the $22.36 represents the cost of gear lubricant & transmission fluid. plus 30%, used in conjunction with "V" operation V4131.

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

Refer to the Chevrolet Claims Processing Manual for details on Product Campaign Claim submission.

Dear Chevrolet Owner:

This notice has been sent to inform you that Chevrolet Motor Division is conducting a recall campaign that includes your vehicle.

REASON FOR THIS RECALL

General Motors has determined that certain 1988 Chevrolet C/K 10-30 Series Trucks equipped with 4-speed manual transmission may have been built with a transmission and transmission shift lever which could remain in reverse after being put in that gear.

WHAT WE WILL DO

To correct this condition on your vehicle, the transmission cover assembly in your truck will be replaced. This service will be completed at no charge to you.

WHAT YOU SHOULD DO

Please contact your Chevrolet dealer to arrange a service date. Instructions for performing this service have been sent to your dealer. It is estimated that parts will be available to your dealer on September 1, 1987. The labor time necessary to replace the transmission cover assembly in your vehicle will vary from 1-1/2 hours to 2 hours. Please ask your dealer if you wish to know how much additional time will be needed to process your vehicle.

The enclosed 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 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 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.