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 the exhaust camshaft sprocket bolts and discard.
  8. Slide the camshaft sprockets forward.

  9. Object Number: 412191  Size: SH
  10. Mark the bearing caps to ensure that the bearing caps 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 bearing caps.
  13. Remove the exhaust camshaft.

  14. Object Number: 412194  Size: SH
  15. Remove the camshaft roller followers.

  16. Object Number: 412197  Size: SH
  17. Remove the hydraulic element lash adjusters.

Installation Procedure


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

  2. Object Number: 412197  Size: SH
  3. Install the hydraulic element lash adjusters.

  4. Object Number: 412194  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: 412191  Size: SH
  9. Install the exhaust camshaft.
  10. Install the camshaft bearing caps.
  11. 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.

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

  14. Install camshaft sprockets onto the camshafts.
  15. Hand tighten NEW camshaft sprocket bolts.
  16. Remove the J 43655 .

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


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

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