GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

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

  2. Object Number: 187021  Size: SH
  3. Rotate the crankshaft until the timing marks in the following locations are aligned:
  4. • The camshaft alignment pin (4).
    • The timing chain dampener (1) to the crankshaft sprocket (2).

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

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

  8. Object Number: 760405  Size: SH
  9. Remove the crankshaft sprocket.

  10. Object Number: 59271  Size: SH
  11. Remove the timing chain dampener bolts.
  12. Remove the timing chain dampener.

  13. Object Number: 96021  Size: SH
  14. If necessary, remove the camshaft thrust plate bolts.
  15. Remove the camshaft thrust plate.
  16. Clean and inspect the timing chain and the gears. Refer to Camshaft Timing Chain and Sprocket Cleaning and Inspection .

Installation Procedure


    Object Number: 96021  Size: SH
  1. If removed, install the camshaft thrust plate.
  2. Notice: Refer to Fastener Notice in the Preface section.

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


    Object Number: 760405  Size: SH
  5. Install the crankshaft sprocket.
  6. Apply engine oil supplement (EOS) GM P/N 1052367 (Canadian P/N 992869), or equivalent, to the sprocket thrust surface.

  7. Object Number: 59271  Size: SH
  8. Install the timing chain dampener.
  9. Install the timing chain dampener bolts.
  10. Tighten
    Tighten the 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: 187021  Size: SH
  15. Align the crankshaft timing mark (2) to the timing mark on the bottom of the timing chain dampener (1).
  16. Align the timing mark on the camshaft gear, center line of the locator hole (4), with the timing mark on the top of the chain dampener (3).
  17. Align the dowel in the camshaft with the dowel hole in the camshaft sprocket (1).

  18. Object Number: 190538  Size: SH

    Important: Draw the camshaft sprocket onto the camshaft using the mounting bolt.

  19. Install the camshaft sprocket bolt.
  20. Tighten
    Tighten the 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 .