Chevrolet Silverado / GMC Sierra. Manual - part 188
Fig. 628: View Of Crankshaft Rear Oil Housing
Courtesy of GENERAL MOTORS CORP.
3. Install the crankshaft rear oil housing onto the crankshaft rear oil seal housing retainer stud.
4. Install the crankshaft rear oil seal housing nut and bolts.
Tighten: Tighten the crankshaft rear oil seal housing nut and bolts to 12 N.m (106 lb in).
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado
Fig. 629: Identifying Crankshaft Rear Oil Seal
Courtesy of GENERAL MOTORS CORP.
5. Inspect the J 35621-B flange for imperfections that may damage the crankshaft rear oil seal.
See Special Tools. Minor imperfections may be removed with a fine grade emery cloth.
6. Clean the crankshaft sealing surface with a clean, lint free towel. Inspect the lead-in edge of
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
the crankshaft for burrs or sharp edges that could damage the rear main oil seal. Remove the
burrs or sharp edges with a fine grade emery cloth before proceeding.
7. Carefully remove the protection sleeve from the NEW crankshaft rear oil seal.
Fig. 630: Identifying Crankshaft Rear Oil Seal
Courtesy of GENERAL MOTORS CORP.
8. Install the crankshaft rear oil 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.
IMPORTANT: Do not apply or use any oil lubrication on the crankshaft rear
oil seal or seal installer. Do not touch the sealing lip of the
oil seal once the protective sleeve is removed.
NOTE:
Proper alignment of the crankshaft rear oil seal is critical.
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado
10. Install the crankshaft rear oil seal onto the crankshaft and into the crankshaft rear oil seal
housing.
1. Turn the J 35621-B wing nut clockwise until the crankshaft rear oil seal is installed
near to flush and square to the crankshaft rear oil seal housing. See Special Tools.
Increased resistance will be felt when the crankshaft rear oil seal has reached the
bottom of the crankshaft rear oil seal housing bore.
2. Turn the J 35621-B wing nut counterclockwise to release the J 35621-B from the
crankshaft rear oil seal. See Special Tools.
11. Remove the J 35621-B from the crankshaft. See Special Tools.
12. Wipe off any excess engine oil with a clean rag.
PISTON, CONNECTING ROD, AND BEARING INSTALLATION
Tools Required
J 8037 Ring Compressor. See Special Tools.
J 8087 Cylinder Bore Gage
J 45059 Angle Meter. See Special Tools.
Piston Selection
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: Powdered metal connecting rods and rod bearing caps are NOT
interchangeable, and must be assembled with the mating
surfaces properly oriented and aligned. Piston, piston pin, and
connecting rod are to be serviced as an assembly.
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado