GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 5825-A Crankshaft Gear Installer
    • J 5590 Crankshaft Gear Installer

Removal Procedure


    Object Number: 69450  Size: SH
  1. Remove the engine front cover and the crankshaft position reluctor ring. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .
  2. Important: Once the engine front cover is removed, do not re-install it.

    Always install a NEW engine front cover.


    Object Number: 344371  Size: SH
  3. Rotate the crankshaft until:
  4. • The number one cylinder is at top dead center (TDC) of the compression stroke
    • The timing marks on both sprockets line up

    Object Number: 500645  Size: SH
  5. Remove the camshaft sprocket bolts.
  6. Remove the camshaft sprocket and the camshaft timing chain.

  7. Object Number: 11506  Size: SH
  8. Use the J 5825-A in order to remove the crankshaft sprocket.
  9. Remove the woodruff key (crankshaft balancer) if necessary.

Installation Procedure


    Object Number: 182847  Size: SH
  1. Install the woodruff key (crankshaft balancer) into the crankshaft, if removed.

  2. Object Number: 32066  Size: SH
  3. Align the keyway of the crankshaft sprocket with the woodruff key (crankshaft balancer).
  4. Use the J 5590 and a hammer in order to install the crankshaft sprocket.
  5. Make sure that the number 1 piston is still at TDC of the compression stroke.
  6. Align the timing marks on both sprockets. Look to ensure that the crankshaft sprocket alignment mark is in the 12 O'clock position.

  7. Object Number: 500645  Size: SH
  8. Install the camshaft sprocket and the timing chain. The camshaft sprocket alignment mark must be in the 6 O'clock position.
  9. 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.

  10. Install the camshaft sprocket bolts.
  11. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  12. Be sure to align the camshaft and the crankshaft sprocket alignment marks.
  13. Install the crankshaft position sensor reluctor ring and the engine front cover. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .