GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

    • J 28509-A Crankshaft Sprocket Remover
    • J 41371 Reluctor Wheel Remover.
  1. Open the hood.
  2. Caution: Before servicing any electrical component, the ignition and start switch must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

  3. Disconnect the battery negative cable from the battery. Refer to Battery Cable in Engine Electrical.
  4. Remove upper fan shroud from the radiator. Refer to Fan Shroud Replacement .
  5. Rotate the engine until the timing marks on the crankshaft balancer and the engine front cover are on TDC.
  6. Remove the drive belt from the vehicle. Refer to Drive Belt Replacement
  7. Raise the vehicle and support with safety stands. Refer to Lifting and Jacking the Vehicle in General Information.
  8. Remove the lower fan shroud from the radiator. Refer to Fan Shroud Replacement
  9. Remove the crankshaft balancer from the crankshaft. Refer to Crankshaft Balancer Replacement .
  10. Remove the water pump from the engine block. Refer to Water Pump Replacement .
  11. Remove the engine front cover from the engine block. Refer to Engine Front Cover Replacement .

  12. Object Number: 11503  Size: SH

    Important: If the crankshaft position reluctor ring is removed, a new crankshaft position reluctor ring sensor must be installed.

  13. Aligned the timing marks on the camshaft and crankshaft gears.
  14. Use the J 41371 to remove the crankshaft reluctor ring from the crankshaft. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .

  15. Object Number: 65453  Size: SH
  16. Remove the camshaft sprocket retaining bolts.
  17. Remove the timing chain and camshaft sprocket.

  18. Object Number: 65848  Size: SH
  19. Use the J 28509-A to remove the crankshaft sprocket.

Installation Procedure

Tools Required

J 22102 Crankshaft Sprocket Installer


    Object Number: 65850  Size: SH

    Important: Ensure the following conditions exist:

       • The camshaft and the crankshaft timing marks are aligned
       • The camshaft dowel pin and the camshaft sprocket holes are properly aligned
       • The gears and the chain mesh properly

  1. Use the J 22102 to install the crankshaft sprocket.

  2. Object Number: 65453  Size: SH

    Notice: Do not hammer the camshaft sprocket onto the camshaft. To do so may dislodge the rear camshaft plug and damage the camshaft.

  3. Install the timing chain and sprocket to the camshaft.
  4. 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.

  5. Install the camshaft retaining bolts to the camshaft.
  6. Tighten
    Tighten the retaining bolts to 12 N·m (106 lb in)


    Object Number: 65453  Size: SH
  7. Install the timing chain and sprocket to the camshaft.
  8. Install the engine front cover to the engine block. Refer to Engine Front Cover Replacement .
  9. Install a new crankshaft position reluctor ring to the crankshaft. Refer to Crankshaft Position Sensor Reluctor Ring Replacement .
  10. Install the crankshaft balancer to the crankshaft. Refer to Crankshaft Balancer Replacement .
  11. Install the water pump to the engine block. Refer to Water Pump Replacement .
  12. Install the lower fan shroud to the radiator. Refer to Fan Shroud Replacement .
  13. Lower the vehicle.
  14. Install the drive belt to the vehicle. Refer to Drive Belt Replacement .
  15. Install the upper fan shroud to the radiator. Refer to Fan Shroud Replacement .
  16. Connect the battery negative cable to the battery. Refer to Battery Cable in Engine Electrical.
  17. Close the hood.