GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 43655 Sprocket Holding Tool

Removal Procedure

  1. Remove the camshaft cover. Refer to Camshaft Cover Replacement .

  2. Object Number: 412167  Size: SH
  3. Remove the upper timing chain guide.

  4. Object Number: 758310  Size: SH
  5. Install the J 43655 .

  6. Object Number: 758314  Size: SH
  7. Remove both the intake and exhaust camshaft sprocket bolts and discard.
  8. Slide the camshaft sprockets forward.

  9. Object Number: 412170  Size: SH
  10. Mark the caps to ensure they are installed in the original position.
  11. Important: Remove each bolt on each cap one turn at a time until there is no spring tension on the camshaft.

  12. Remove the caps.
  13. Remove the intake camshaft.

  14. Object Number: 412183  Size: SH
  15. Remove the camshaft roller followers.

  16. Object Number: 412185  Size: SH
  17. Remove the hydraulic lash adjusters.

Installation Procedure


    Object Number: 412514  Size: SH
  1. Lubricate the valve tips.

  2. Object Number: 412185  Size: SH
  3. Install the hydraulic lash adjusters.

  4. Object Number: 412183  Size: SH
  5. Install the camshaft roller followers.

  6. Object Number: 466536  Size: SH
  7. Ensure that the alignment notches are aligned with the camshaft sprocket.

  8. Object Number: 412516  Size: SH
  9. Install the intake camshaft.
  10. Install the camshaft caps.
  11. Notice: Refer to Fastener Notice in the Preface section.

  12. Tighten the camshaft cap bolts in increments of 3 turns until they are seated.
  13. Tighten
    Tighten the camshaft cap bolts to 10 N·m (89 lb in).


    Object Number: 412517  Size: SH
  14. Apply a 3.5 mm (0.138 in) bead of sealant to the rear intake camshaft bearing cap. Refer to Adhesives, Fluids, Lubricants, and Sealers for the correct part number.
  15. Install the rear intake camshaft cap bolts.
  16. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  17. Install camshaft sprockets onto the camshafts.
  18. Hand tighten NEW camshaft sprocket bolts.
  19. Remove the J 43655 .

  20. Object Number: 630311  Size: SH
  21. Tighten the camshaft sprocket bolts.
  22. Tighten
    Tighten the bolts to 85 N·m (63 lb ft) plus 30 degrees.


    Object Number: 412167  Size: SH
  23. Install the upper timing chain guide.
  24. Tighten
    Tighten the upper timing chain guide to 10 N·m (89 lb in).

  25. Install the camshaft cover. Refer to Camshaft Cover Replacement .