Sierra Classic 1500 4WD V8-5.3L (2007)
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Place a drain pan under the vehicle.
3. Remove the propeller shaft. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement.
4. Remove the case extension housing rear oil seal. Use a flat bladed tool and carefully pry the seal from the housing.
5. Inspect the case extension housing for damage. Replace the extension housing if necessary. Refer to Transmission Extension Housing Assembly
Replacement.
Installation Procedure
1. Lubricate the inside diameter of the new seal with J 36850.
2. Use the J 21426 with a soft faced mallet to install the seal.
3. Install the seal to the extension housing.
4. Install the propeller shaft. Refer to One-Piece Propeller Shaft Replacement or Two-Piece Propeller Shaft Replacement.
5. Remove the drain pan and lower the vehicle.
6. Fill the transmission to the proper level with DEXRON(r) III transmission fluid. Refer to Transmission Fluid Check.
