SHUDDER/VIBR. UPON TCC DISENGAGE (REPLACE CLUTCH). GMC Truck S15 Pickup - 4WD 1992

For 1990-2009 cars

# SHUDDER/VIBR. UPON TCC DISENGAGE (REPLACE CLUTCH)

#### SUBJECT: SHUDDER/VIBRATION UPON TCC DISENGAGEMENT (REPLACE TORQUE CONVERTER)

#### MODELS: 1992 TYPHOON

#### CONDITION:

--------- Owners of some 1992 Typhoons built before March 2, 1992 (transmission Julian date 2 062) may comment that there is a vibration or shudder when the TCC disengages while under a slight acceleration.

#### CAUSE:

----- The TCC vibration or shudder may be a result of the damper springs in the TCC bottoming out.

#### CORRECTION:

---------- Transmission assemblies built after Julian date 2 062 will already have the revised torque converters. If the Julian date is before 2 062, the transmission was built without the revised torque converter. To correct this condition replacement of the torque converter with a revised unit (P/N 8687990) is necessary.

#### SERVICE PROCEDURE:

1. Check the Julian date of transmission as shown in the "1992 Sonoma and Jimmy Service Manual", Section 7 Automatic Transmission, page 7A-l, Figure-1. If the Julian date is before 2 062 proceed to step 2.

2. Refer to Section 7 Automatic Transmission, Preliminary Checking Procedure and Noise and Vibration Analysis, page 7A-3 and the Torque Converter Clutch (TCC) Diagnosis on page 7Al-5 to verify the shudder or vibration complaint. If complaint is confirmed, proceed to step 3.

3. Remove the transmission as detailed in the "1992 Syclone, Typhoon and Sonoma GT Service Manual Supplement", page 7Al-9.

4. Replace the torque converter.

5. Reinstall the transmission.

#### NOTE: When Reinstalling the transmission, make sure that the transfer case TV cable, and fuel lines are properly routed to prevent rattles by these components coming in contact with the floor panel. Also, inspect the positive battery cable for signs of contact with the exhaust system, replace if damaged.

#### SERVICE PARTS INFORMATION

Part Number Description ----------- ----------- 8687990 1 Torque Converter Clutch

Parts are expected to be available on 10/12/92. In case of limited inventory, parts will be placed on 400 control to waive VIP surcharges. Only verifiable emergency orders will be accepted. GMSPO will make every effort to obtain parts. However, the part will be shipped premium transportation at the dealer's expense and all other order types will be placed on backorder until the 400 control is removed.

#### WARRANTY INFORMATION

Labor Operation: K7020

Labor Time: 4.6 H rs.

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.