GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 7872 (SA 9179NE) Magnetic Base Dial Indicator Set

  1. Clean the camshaft with cleaning solvent.

  2. Object Number: 230090  Size: SH

    Caution: Bodily injury may occur if the cleaning solvent is inhaled or exposed to the skin.

  3. Inspect the camshaft for the following conditions:
  4. • Scored camshaft bearing journals (1)
    • Damaged camshaft lobes (2)
    • Damaged camshaft sprocket locator pins (3)
    • Damaged threads (4)
    • Damage to the camshaft reluctor tooth (5)

    Object Number: 35212  Size: SH
  5. Measure the camshaft journals using a micrometer.
  6. If the camshaft journals are not within specifications, replace the camshaft.


    Object Number: 230102  Size: SH
  7. Measure the camshaft runout using the J 7872 (SA 9179NE).
  8. 4.1. Mount the camshaft in V-blocks between the centers.
    4.2. Use the J 7872 (SA 9179NE) in order to measure the intermediate camshaft journal.
  9. Measure the camshaft lobe lift using the J 7872 (SA 9179NE).
  10. 5.1. Lubricate the camshaft using P/N 12345501 or the equivalent.
    5.2. Set the camshaft on V-blocks.
    5.3. Use the J 7872 (SA 9179NE) in order to measure the lobe lift.
  11. If the runout or lobe lift is not within specifications, replace the camshaft.