CENTER BEARING ISOLATOR WEAR AND PROP SHAFT NOISE
Model and Year: 1988 EXTENDED CAB K1, 2, 3
The rear propeller shaft in the 1988 K extended cab is a steel two piece design with a center bearing. As the suspension articulates, the shaft between the transfer case and the center bearing may be drawn rearward causing contact with the center bearing isolator. The result could be a noticeable noise and center bearing wear.
The 2 piece propeller shaft in the 1989 K extended cab has been redesigned. The new center bearing has a rear extension. The transfer case to center bearing prop shaft has a necked down 3" spline and the rear prop shaft has a pop-on seal in front of the slip yoke.
When encountered, center bearing isolator wear and prop shaft noise in 1988 K extended cab can be corrected by replacing the two rear propeller shafts and center bearing using the new design (1989) parts and the procedure in the 1988 C/K Service Manual, Section 4A.
Parts
Parts are currently available from GMSPO.
Front Propeller Shaft Rear Propeller Shaft Model Part Number * Part Number ----- --------------------- ---------------------- K10953-M20 15622415 15622431
K10953+M20 15622417 15622427
Front Propeller Shaft Rear Propeller Shaft Model Part Number * Part Number ----- --------------------- -------------------- K20953 15622417 15622428
K30953-RO5,-L19 15622417 15622428
K30953-RO5,+L19 15622417 15622429
* Front Propeller Shaft P/N includes Center Bearing
Note: M20 = 117mm 4 Spd. Transmission R05 = Dual Rear wheel L19 = 7.4L TBI
For vehicles repaired under warranty, use:
Labor Op: F1280
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.
