Front Differential Output Shaft Seals - Replacement

File In Section: 4 - Drive Axle

Bulletin No.: 56-43-02

Date: October, 1995

INFORMATION

Subject:
Replacing Front Differential Output Shaft Seals

Models:
1988-96 Chevrolet and GMC Truck K Models

Important:
A copy of this service bulletin should be given to the appropriate warranty administration personnel.

The purpose of this bulletin Is to discuss the following two important points as they relate to front differential output shaft seal replacement:

^ Proper Labor Operation Usage.

^ Proper Drive Axle (Halfshaft) Handling To Prevent Damage to the New Inboard and Outboard Boot (Seal).

Bulletin No.: 56-43-02:

For reference purposes, Figure 1 shows a layout of the front drive system.

Proper Labor Operation Usage

If the replacement of the front axle output shaft seal(s) becomes necessary and the vehicle and repair are subject to the applicable warranty, only the following Labor Operation should be used:

F1440: Seals Front Differential Output Shaft - Replace Right

F1441: Seals Front Differential Output Shaft - Replace Left

F1447: Seals Front Differential Output Shaft - Replace Both

Important:
This labor operation includes the time needed for removal and replacement of the front drive axle (halfshaft). DO NOT submit an additional claim for Front Drive Halfshaft R & R.

Proper Drive Axle (Halfshaft) Handling to Prevent Inboard and Outboard Boot Damage

When performing the output shaft seal replacement procedure described in the service manual, precautions should be taken to prevent damage to the inboard and outboard drive axle (halfshaft) boots (seals). The boots (seals) are delicate and critical to the performance of the halfshaft. Take the following precautions when performing the procedure:

Remove the drive axle (halfshaft) completely from the vehicle to gain access to the output shaft. DO NOT try to remove the output shaft without first removing the drive axle (halfshaft) from the vehicle. Damage to halfshaft boots (seals) may result. Furthermore, attempts to reinstall the output shaft into the differential with the halfshaft pushed off to one side may result In damage to the output shaft seal.

^ Avoid contact between the inboard and outboard halfshaft boots (seals) and any surface which could cause a cut, nick, or abrasion.

^ When loosening or tightening the 6 bolts which secure the halfshaft to the output shaft, care should be taken to prevent tools from contacting the inboard halfshaft boot (seal).