GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

J 5825-A Crankshaft Sprocket Remover

  1. Remove the engine front cover. Refer to Engine Front Cover Replacement .

  2. Object Number: 644213  Size: SH
  3. Rotate the crankshaft until the timing marks in the following locations are aligned:
  4. • The timing chain dampener to the crankshaft sprocket (2).
    • The timing chain dampener to the camshaft sprocket locator hole (1).

    Object Number: 190538  Size: SH
  5. Remove the camshaft sprocket bolt.

  6. Object Number: 190539  Size: SH
  7. Remove the camshaft sprocket.

  8. Object Number: 54291  Size: SH
  9. Remove the timing chain.

  10. Object Number: 54293  Size: SH
  11. Use the J 5825-A in order to remove the crankshaft sprocket.

  12. Object Number: 59271  Size: SH
  13. Remove the timing chain dampener bolts.
  14. Remove the timing chain dampener.

  15. Object Number: 96021  Size: SH
  16. If necessary remove the camshaft thrust plate bolts.
  17. Remove the camshaft thrust plate.
  18. Clean and inspect the timing chain and gears. Refer to Timing Chain and Sprockets Clean and Inspect .

Installation Procedure

Tools Required

J 38612 Crankshaft Sprocket Installer


    Object Number: 96021  Size: SH
  1. If removed install the camshaft thrust plate.
  2. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the camshaft thrust plate bolts.
  4. Tighten
    Tighten the camshaft thrust plate bolts to 10 N·m (89 lb in).


    Object Number: 54294  Size: SH
  5. Install the crankshaft sprocket using the J 38612 .
  6. Remove the J 38612 .
  7. Apply Engine Oil Supplement (EOS) GM P/N 1052367 or equivalent to the sprocket thrust surface.

  8. Object Number: 59271  Size: SH
  9. Install the timing chain dampener to the block.
  10. Tighten
    Tighten the timing chain dampener bolts to 21 N·m (15 lb ft).


    Object Number: 54291  Size: SH
  11. Install the timing chain onto the camshaft gear.

  12. Object Number: 190539  Size: SH
  13. Hold the camshaft sprocket with the chain hanging down, and install the chain to the crankshaft gear.

  14. Object Number: 644213  Size: SH
  15. Align the crankshaft timing mark to the timing mark on the bottom of the timing chain dampener (2).
  16. Align the camshaft timing mark to the timing mark on the top of the timing chain dampener (2).

  17. Object Number: 190538  Size: SH
  18. Install the camshaft sprocket bolt.
  19. Draw the camshaft sprocket onto the camshaft using the mounting bolt.
  20. Tighten
    Tighten the camshaft sprocket bolt to 140 N·m (103 lb ft).

  21. Coat the crankshaft and camshaft sprocket with engine oil.
  22. Install the engine front cover. Refer to Engine Front Cover Replacement .