GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 44212 Camshaft Holding Tool

Removal Procedure

  1. Remove the right secondary camshaft drive chain tensioner. Refer to Secondary Camshaft Drive Chain Tensioner Replacement - Right Side .
  2. Remove the camshaft position sensor. Refer to Camshaft Position Sensor Replacement in Engine Controls-4.0L.
  3. Remove the right camshaft cover. Refer to Camshaft Cover Replacement - Right Side .

  4. Object Number: 517164  Size: SH
  5. Ensure both camshaft sprocket drive pins are at the top of their rotation.

  6. Object Number: 650538  Size: SH

    Caution: The camshaft holding tools must be installed on the camshafts to prevent camshaft rotation. When performing service to the valve train and/or timing components, valve spring pressure can cause the camshafts to rotate unexpectedly and can cause personal injury.

  7. Install the J 44212 over the camshafts.

  8. Object Number: 749349  Size: SH
  9. Remove the mechanics wire (1) supporting the right secondary camshaft drive chain shoe (3).
  10. Remove the engine front cover bolt (2) from the front of the engine.

  11. Object Number: 749353  Size: SH
  12. Use an open end wrench on the hex cast into the camshaft in order to prevent the camshaft from rotating when removing the camshaft sprocket bolt.

  13. Object Number: 650548  Size: SH
  14. Remove the right exhaust camshaft sprocket bolt.
  15. Slide the right exhaust camshaft sprocket off of the camshaft and remove the right secondary camshaft drive chain from the camshaft sprocket teeth.

  16. Object Number: 685335  Size: SH
  17. Lift the right secondary camshaft drive chain from the camshaft intermediate drive shaft sprocket teeth.
  18. Remove the right secondary camshaft drive chain from the engine.
  19. Clean and inspect the camshaft timing drive components. Refer to Camshaft Timing Drive Components Cleaning and Inspection .

Installation Procedure


    Object Number: 685335  Size: SH
  1. Install the right secondary camshaft drive chain by sliding the chain down through the right cylinder head and placing the chain on the right intake camshaft sprocket.
  2. Route the right secondary camshaft drive chain around the outer row of the camshaft intermediate drive shaft sprocket teeth.

  3. Object Number: 517164  Size: SH
  4. Install the right exhaust camshaft sprocket into the right secondary camshaft drive chain.
  5. Install the right exhaust camshaft sprocket onto the camshaft. The camshaft sprocket notch marked RE (right exhaust) engages the exhaust camshaft pin.

  6. Object Number: 749353  Size: SH
  7. Use an open end wrench on the hex cast into the camshaft in order to prevent the camshaft from rotating when tightening the camshaft sprocket bolt.
  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. Install the right exhaust camshaft sprocket bolt.
  10. Tighten
    Tighten the camshaft sprocket bolt to 120 N·m (89 lb ft).

  11. Install the right secondary camshaft drive chain tensioner. Refer to Secondary Camshaft Drive Chain Tensioner Replacement - Right Side .

  12. Object Number: 650538  Size: SH
  13. Remove the J 44212 from the camshafts.
  14. Install the right camshaft cover. Refer to Camshaft Cover Replacement - Right Side .
  15. Install the camshaft position sensor. Refer to Camshaft Position Sensor Replacement in Engine Controls-4.0L.