Case Extension and Gasket Replacement

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Fig 1: Extension Housing and Seal Replacement

Courtesy of GENERAL MOTORS COMPANY

Callout	Component Name
NOTE: The extension housing and drive shaft flange (yolk) on this vehicle are serviced as a complete assembly. The drive shaft flange seal is a dust shield used to protect the sealed drive shaft flange bearing that is pressed into the extension housing. The drive shaft flange is pressed into the drive shaft flange bearing, and is not serviceable. The extension housing should NOT contain any transmission fluid. If transmission fluid is present in the extension housing, replacement of the output shaft seal is necessary. Refer to Transmission Output Shaft Seal Replacement (Four Wheel Drive) . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the propeller shaft. Refer to Rear Propeller Shaft Replacement . Support the transmission with a suitable jack. Remove the transmission mount assembly. Refer to Transmission Mount Replacement (2WD) , Transmission Mount Replacement (4WD) .
1	Case Extension Housing Bolt (Qty: 6) CAUTION: Refer to Fastener Caution . Tighten 50 N.m (37 lb ft)
2	Case Extension Housing Assembly Serviced as a complete assembly as shown. There is no gasket or seal between the extension housing and transmission case.

Callout

Component Name

NOTE:

The extension housing and drive shaft flange (yolk) on this vehicle are serviced as a complete assembly. The drive shaft flange seal is a dust shield used to protect the sealed drive shaft flange bearing that is pressed into the extension housing. The drive shaft flange is pressed into the drive shaft flange bearing, and is not serviceable. The extension housing should NOT contain any transmission fluid. If transmission fluid is present in the extension housing, replacement of the output shaft seal is necessary. Refer to Transmission Output Shaft Seal Replacement (Four Wheel Drive) .

Preliminary Procedures

Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
Remove the propeller shaft. Refer to Rear Propeller Shaft Replacement .
Support the transmission with a suitable jack.
Remove the transmission mount assembly. Refer to Transmission Mount Replacement (2WD) , Transmission Mount Replacement (4WD) .

Case Extension Housing Bolt (Qty: 6)

CAUTION:

Refer to Fastener Caution .

Tighten
50 N.m (37 lb ft)

Case Extension Housing Assembly

Serviced as a complete assembly as shown.
There is no gasket or seal between the extension housing and transmission case.