GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • EN-47623 Rear Main Seal Installer
    • J 8092 Drive Handle
    • J 45059 Torque Angle Meter

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  3. Drain the engine oil. Refer to Engine Oil and Oil Filter Replacement .
  4. Remove the engine flywheel. Refer to Engine Flywheel Replacement .
  5. Remove the oil pan. Refer to Oil Pan Replacement .

  6. Object Number: 406047  Size: SH
  7. Remove the crankshaft rear oil seal housing bolts.
  8. Remove the crankshaft rear oil seal housing.
  9. Remove the crankshaft rear oil seal.
  10. Important: Ensure not to damage the crankshaft outside diameter surface with any tool.

  11. Remove the gasket from the crankshaft rear oil seal housing and the cylinder block.
  12. Inspect the inside diameter of the bore. Correct or replace the crankshaft rear oil seal housing if necessary.
  13. Inspect the crankshaft for nicks of burrs on the surface that contacts the seal.
  14. Repair or replace the crankshaft if necessary.

Installation Procedure

Notice: Do not apply or use any oil lubrication on the crankshaft rear oil seal, or the seal installer. Do not touch the sealing lip of the oil seal once the protective sleeve is removed. Doing so will damage/deform the seal.

Notice: Clean the crankshaft sealing surface with a clean, lint free towel. Inspect lead-in edge of crankshaft for burrs/sharp edges that could damage the rear main oil seal. Remove burrs/sharp edges with crocus cloth before proceeding.

  1. Clean and inspect the crankshaft rear oil seal housing making sure it is free of any foreign material.
  2. With all bolts removed from the housing, place it face up on a flat clean surface.
  3. Carefully remove the protection sleeve from the NEW rear oil seal.

  4. Object Number: 1437953  Size: SH

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

  5. Install the seal onto EN-47623 by placing the seal on an angle and using a twisting motion until it is fully seated.

  6. Object Number: 1437955  Size: SH
  7. Place EN-47623 along with J 8092 onto the housing as shown and apply a constant downward force until the seal is fully seated.

  8. Object Number: 1481329  Size: SH
  9. Clean the crankshaft sealing surface with a clean, lint free towel. Inspect the crankshaft sealing surface and leading edge of the crankshaft for burrs/sharp edges that could damage the rear main oil seal. Remove any burrs or sharp edges with crocus cloth prior to proceeding.
  10. Important: Always install a new crankshaft rear oil seal housing gasket.

  11. Install a NEW crankshaft rear oil seal housing gasket and the housing onto the engine.
  12. Important: The plastic inserts found in the rear oil seal housing retaining bolts are used to aid production assembly only. The inserts are not required for service.

  13. Install the crankshaft rear oil seal housing bolts finger tight.

  14. Object Number: 406048  Size: SH
  15. Place a straight edge on the engine block oil pan flange and the crankshaft rear oil seal housing flange. Use a feeler gage to ensure there is no more than 0.10 mm (0.004 in) step on each side. If necessary, gently rotate the crankshaft rear oil seal housing to make the step equal on each side.
  16. Notice: Refer to Fastener Notice in the Preface section.

  17. Tighten the crankshaft rear oil seal housing bolts.
  18. Tighten
    Tighten the bolts a first pass to 15 N·m (11 lb ft). Using the J 45059 , tighten the bolts a final pass an additional 50 degrees.

  19. Recheck the step height on each side to ensure the crankshaft rear oil seal housing did not move. If the step height is beyond specification, reinstall the crankshaft rear oil seal housing and measure the step again. Replace the crankshaft rear oil seal housing if the clearance is still beyond specification.