GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 44212 Camshaft Holding Tool


    Object Number: 685372  Size: SH
  1. Install the left secondary camshaft drive chain guide.

  2. Object Number: 685368  Size: SH
  3. Loosely install the lower left secondary camshaft drive chain guide bolt.

  4. Object Number: 685367  Size: SH
  5. Install the left secondary camshaft drive chain shoe.
  6. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 685364  Size: SH
  7. Install the left secondary camshaft drive chain shoe bolt.
  8. Tighten
    Tighten the left secondary camshaft drive chain shoe bolt to 25 N·m (18 lb ft).


    Object Number: 685362  Size: SH
  9. Install the left secondary camshaft drive chain by sliding the chain down through the left cylinder head and placing the chain on the end of the camshafts.
  10. Route the left secondary camshaft drive chain around the inner row of the intermediate drive chain sprocket teeth.

  11. Object Number: 1207121  Size: SH
  12. Install the left intake and exhaust camshaft sprockets into the left secondary camshaft drive chain.

  13. Object Number: 517145  Size: SH

    Important: Do not use the stamped indicator marks for perpendicular alignment when installing the timing chain.

  14. Install the left intake and exhaust camshaft sprockets onto the camshafts. The camshaft sprocket slot marked "LI" which indicates left intake, engages the intake camshaft pin and the camshaft sprocket slot marked "LE" which indicates left exhaust, engages the exhaust camshaft pin.

  15. Object Number: 53007  Size: SH
  16. If necessary, use an open wrench on the hex cast near the front of each camshaft to help align the sprocket slot to the camshaft pin.
  17. Loosely install the left intake and exhaust camshaft sprocket bolts.

  18. Object Number: 517149  Size: SH
  19. Ensure the perpendicular alignment of the left intake and exhaust camshaft sprocket slots and camshaft pins to the cylinder head.

  20. Object Number: 650538  Size: SH
  21. Install the J 44212 to the left cylinder head camshafts.

  22. Object Number: 685354  Size: SH
  23. Install the upper left secondary camshaft drive chain guide bolt.
  24. Tighten
    Tighten BOTH the upper and lower left secondary camshaft drive chain guide bolts to 25 N·m (18 lb ft).


    Object Number: 53004  Size: SH
  25. Collapse the left secondary camshaft drive chain tensioner using the following procedure:
  26. 14.1. Rotate the ratchet release lever counterclockwise and hold.
    14.2. Collapse the left secondary camshaft drive chain tensioner shoe and hold.
    14.3. Release the ratchet lever and slowly release the pressure on the shoe.
  27. When the ratchet lever moves to the first detent a click should be heard and felt. Insert a pin through the hole in the release lever in order to lock the left secondary camshaft drive chain tensioner shoe in the collapsed position.

  28. Object Number: 685353  Size: SH

    Important: Ensure the left secondary camshaft drive chain tensioner release lever is facing out.

  29. Install the left secondary camshaft drive chain tensioner.
  30. Install the left secondary camshaft drive chain tensioner bolts.
  31. Tighten
    Tighten the left secondary camshaft drive chain tensioner bolts to 25 N·m (18 lb ft).

  32. Remove pin from left secondary camshaft drive chain tensioner lever.