Case Extension and Gasket Replacement

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Case Extension Housing and Seal Replacement

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
IMPORTANT: 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 . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the propeller shaft. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement . Support the transmission with a suitable jack. Remove the transmission mount assembly. Refer to Transmission Mount Replacement (2WD) or Transmission Mount Replacement (4WD) .
1	Case Extension Housing Bolt (Qty: 6) NOTE: Refer to Fastener Notice . Tighten: 50 N.m (37 lb ft)
2	Case Extension Housing Assembly Tip: Serviced as a complete assembly as shown. There is no gasket or seal between the extension housing and transmission case.

Callout

Component Name

IMPORTANT: 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 .

Preliminary Procedures

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

Case Extension Housing Bolt (Qty: 6)

NOTE: Refer to Fastener Notice .

Tighten: 50 N.m (37 lb ft)

Case Extension Housing Assembly
Tip:

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