GM Service Manual Online
For 1990-2009 cars only

    Object Number: 648577  Size: SH
  1. Verify that the keyway (2) on the crankshaft is positioned properly.

  2. Object Number: 648583  Size: SH
  3. Install the crankshaft sprocket (2) to the crankshaft (1).

  4. Object Number: 648641  Size: SH
  5. Verify that the Knock-pin (1) on the right intake camshaft is aligned with the match mark (2).

  6. Object Number: 648628  Size: SH
  7. Install the right primary sprocket to the intake camshaft with the RH mark facing forward.
  8. 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.

  9. Secure the sprocket (1) with the bolt while holding the intake camshaft (2) with a wrench.
  10. Tighten
    Tighten the bolt to 80 N·m (57.5 lb ft).


    Object Number: 648352  Size: SH
  11. Install the timing chain tensioner (2). Secure with the nut.
  12. Tighten
    Tighten the nut to 27 N·m (19.5 lb ft).


    Object Number: 648622  Size: SH
  13. Install the primary timing chain to the primary right intake sprocket by aligning the right silver link (1) on the chain with the mark (2) on the sprocket.

  14. Object Number: 648579  Size: SH
  15. Apply oil to the inside of the idler sprocket and install the sprocket by aligning the left silver link (1) with the mark (2) on the idler sprocket.

  16. Object Number: 648567  Size: SH
  17. Install the primary timing chain to the crankshaft sprocket by aligning the yellow link (2) on the chain with the mark (3) on the sprocket.
  18. Apply oil to the bearing of the idler sprocket.

  19. Object Number: 648569  Size: SH
  20. Install the primary timing chain to the idler sprocket (1) and secure the sprocket to the engine block with the bolt.
  21. Tighten
    Tighten the bolt to 45 N·m (32.5 lb ft).


    Object Number: 648327  Size: SH
  22. With the latch (2) of the tensioner adjuster returned and the plunger (3) pushed back into the body, insert a retainer (paper clip or similar tool) (1) into the set hole. After inserting the pin, make sure the plunger will not come out.

  23. Object Number: 648354  Size: SH
  24. Install the tensioner adjuster (1) to the engine block and tensioner. Secure with the 2 bolts.
  25. Tighten
    Tighten the bolt to 11 N·m (7.5 lb ft).

  26. Remove the retainer (3) from the tensioner.

  27. Object Number: 648544  Size: SH
  28. Install the timing chain guides (1, 3).
  29. Tighten
    Tighten the bolts to 9 N·m (6.5 lb ft).


    Object Number: 648462  Size: SH
  30. Verify that each timing mark is aligned properly.
  31. Install the left secondary timing chain and tensioner. Refer to Secondary Timing Chain Installation - Left Side .
  32. Install the engine front cover. Refer to Engine Front Cover Installation .
  33. Install the spark plugs. Refer to Spark Plug Replacement in Engine Controls.