S15/T15 Sonoma P/U 2WD V6-262 4.3L VIN W CPI (1994)
Pinion Flange: Customer Interest
Driveline - Launch Shudder
FILE IN SECTION: 4 - Drive Axle
BULLETIN NO.: 56-41-02
DATE: July, 1995
SUBJECT:
Driveline Launch Shudder (Install Newly Designed Propeller Shaft)
MODELS:
1992-93
Chevrolet and GMC Truck S10803 Models
(Pick-up, Regular Cab, and Long Bed)
1992-94
Chevrolet and GMC Truck S10653 Models
(Pick-up, Extended cab, and Short bed)
1992-94
Chevrolet and GMC Truck T10653 Models
(Pick-up, Extended cab, and Short bed)
with 4.3L V-6 Engines (VINs W, Z - RPOs L35, LB4) and Automatic Transmission
CONDITION
Some owners of pick ups with 4.3L V-6 engines (RPOs L35, LB4), equipped with a two-piece rear propeller shaft and an automatic transmission, may
experience a launch shudder condition. This condition may occur from 0-25 mph (0-40 kph) and is more noticeable during hard acceleration when the
vehicle is heavily loaded, or when used as a tow vehicle.
CAUSE
This condition is caused by the driveline angle changes occurring during engine torque and vehicle payload.
CORRECTION
To repair this condition a newly designed rear propeller shaft and pinion flange is released for service to reduce driveline launch shudder during 0-25
mph (0-40 kph).
SERVICE PROCEDURE
Remove or Disconnect (Figures 1, 2, and 3)
Tool Required: J 8614-01 Companion Flange Holder
1.
Place the vehicle on a hoist that will allow free rotation of the rear wheels.
2.
Remove both rear tire wheel and drum assemblies.
3.
Remove and discard existing two piece rear propeller shaft assembly, retaining the straps and fasteners.
4.
Measure the pre-load on the rear axle pinion flange using an inch pound torque wrench, the amount of torque required to turn the pinion (Figure