C 1500 Truck 2WD V6-262 4.3L (1989)
Pressure Plate: All Technical Service Bulletins
Clutch - Shudder On Launch
GMC NUMBER:
91-7C-96
GROUP:
7C Clutch
DATE:
May, 1991
CORPORATE
NUMBER:
167302
SUBJECT:
CLUTCH CHATTER/SHUDDER ON LAUNCH
MODELS:
1988-91 C/K TRUCKS EQUIPPED WITH 4.3L & 5.0L ENGINES AND 4 SPEED & 5 SPEED MANUAL TRANSMISSIONS
Some 1988-91 C/K trucks equipped with 4.3L or 5.0L engines with 4 speed or 5 speed manual transmissions may experience a condition of chatter or
shudder on launch.
Revised clutch discs and matching pressure plates have been released for these vehicles and are available through GMSPO. The clutch discs feature a
revised facing material which will provide smoother engagement and increased wear resistance. These revised discs can be identified by the name stamp
Valeo while the previous discs were stamped Borg Warner. The pressure plates have been revised to work with the discs and must be replaced at the
same time. The revised pressure plates will be marked with the name stamp Luk while the previous pressure plate may be marked with the name stamp
Luk or Borg Warner. The installation of these parts will provide significant improvement in the involved vehicles.
VEHICLES INVOLVED Some 1988-91 C/K trucks equipped with 4.3L or 5.0L engines and 4 speed or 5 speed transmissions built prior to the
following VIN breakpoints:
4.3L/5.0L
GMC
CHEVROLET
Fort Wayne (Z)
MZ516555
MZ159936
Oshawa (1)
M1526826
MI 178933
Pontiac (E)
ME516465
ME152577
SERVICE PROCEDURE The pressure plate and clutch disc should be replaced at the same time as the parts have been
designed to work together. Refer to section 7C of the appropriate service manual for clutch disc and pressure plate replacement procedure.
Important
Before removing the existing pressure plate, note the location of the paint dab on the pressure plate cover. This paint dab indicates the heavy side of the
pressure plate assembly and is aligned with the light side of the engine at the assembly plant. The new pressure plate should be installed with the paint
dab in the same location to preserve the balance of the engine assembly.
SERVICE PARTS INFORMATION
ENGINE
TRANSMISSION
PRESSURE
CLUTCH
PLATE P/N
DISC P/N
4.3L
4 or 5 SPEED
15668537
15666527
5.0L
5 SPEED
15668537
15668527
Parts are currently available from GMSPO.
WARRANTY INFORMATION
For vehicles repaired under warranty use:
LABOR
MODELS
LABOR
OPERATION
TIME
K0800
C1 C2 C3
2.2 hrs.
K0800
K1 K2 K3
3.0 hrs.
Add
K1 K2 K3 with skid plate
0.3 hr.