Chevrolet Silverado / GMC Sierra. Service manual — part 95

Fig. 305: Identifying Crankshaft Rear Oil Seal
Courtesy of GENERAL MOTORS CORP.

5. Inspect the J 35621-B flange for imperfections that may damage the NEW seal. See Special

Tools.

Minor imperfections may be removed with a fine grade emery cloth.

IMPORTANT: Notice the direction of the rear oil seal. The new design seal

is a reverse style as opposed to what has been used in the
past. THIS SIDE OUT has been stamped into the seal as
shown in the graphic.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

6. Remove the sleeve from the seal.

7. Apply 2 to 3 drops of clean engine oil to the outside diameter of the seal.

8. Install the seal onto the J 35621-B . See Special Tools.

9. Install the J 35621-B onto the rear of the crankshaft and hand tighten the tool bolts until

snug. See Special Tools.

10. Install the seal onto the crankshaft and into the housing:

1. Turn the J 35621-B wing nut clockwise until the seal is installed close to flush and

square to the housing. See Special Tools.

Increased resistance will be felt when the seal has reached the bottom of the housing
bore.

2. Turn the J 35621-B wing nut counterclockwise to release the J 35621-B from the

seal. See Special Tools.

11. Remove the J 35621-B . See Special Tools.

12. Wipe off any excess engine oil with a clean rag.

13. Install the engine flywheel. Refer to Engine Flywheel Replacement.

CRANKSHAFT REAR OIL SEAL HOUSING REPLACEMENT

Removal Procedure

IMPORTANT: DO NOT allow oil or any other lubricants to contact the seal

lip surface of the seal.

NOTE:

Proper alignment of the crankshaft rear oil seal is critical.
Install the crankshaft rear oil seal near to flush and square to
the crankshaft rear oil seal housing. Failing to do so may cause
the crankshaft rear oil seal or the crankshaft rear oil seal
installation tool to fail.

IMPORTANT: Do not remove the crankshaft rear oil seal housing if only

replacing the crankshaft rear oil seal.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 306: Crankshaft Rear Oil Seal Housing
Courtesy of GENERAL MOTORS CORP.

1. Remove the oil pan. Refer to Oil Pan Replacement.

2. Remove the engine flywheel. Refer to Engine Flywheel Replacement.

3. Remove the housing bolts and nut.

4. Remove the housing.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 307: Locating Crankshaft Rear Oil Seal Housing Gasket
Courtesy of GENERAL MOTORS CORP.

5. Remove and discard the housing gasket.

6. Clean all the sealing surfaces.

7. Inspect and replace the housing for warping, cracks, wear, or damage.

Installation Procedure

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado