GM Service Manual Online
For 1990-2009 cars only

    Object Number: 2018079  Size: SH
  1. Clamp the camshaft in a vise, and make sure that the camshaft timing gear or sprocket does not rotate.
  2. Remove the bolt and camshaft timing gear or sprocket.
  3. Remove camshaft timing gear assembly.

  4. Object Number: 2017109  Size: SH
  5. Inspect the camshaft for runout.
  6. Place the camshaft on V-blocks.
  7. Using a dial indicator, measure the circle runout at the center journal.
  8. Maximum Circle Runout
    0.03 mm (0.0012 in)

  9. If the circle runout is greater than the maximum, replace the camshaft.

  10. Object Number: 2017110  Size: SH
  11. Inspect the cam lobes.
  12. Using a micrometer, measure the cam lobe heights.
  13. Standard Cam Lobe Height
    47.306 to 47.406 mm (1.8624 to 1.8664 in)

    Minimum Cam Lobe Height
    47.196 mm (1.8581 in)

  14. If any of the cam lobe heights are less than the minimum, replace the camshaft.

  15. Object Number: 2017111  Size: SH
  16. Inspect the camshaft journals.
  17. Using a micrometer, measure the journal diameter.
  18. If the journal diameter is not as specified, check the oil clearance.

  19. Object Number: 2017109  Size: SH
  20. Inspect No. 2 camshaft for runout.
  21. Place the camshaft on V-blocks.
  22. Using a dial indicator, measure the circle runout at the center journal.
  23. Maximum Circle Runout
    0.03 mm (0.0012 in)

  24. If the circle runout is greater than the maximum, replace the camshaft.

  25. Object Number: 2017110  Size: SH
  26. Inspect the cam lobes.
  27. Using a micrometer, measure the cam lobe heights.
  28. Standard Cam Lobe Height
    46.063 to 46.163 mm (1.8135 to 1.8174 in)

    Minimum Cam Lobe Height
    45.953 mm (1.8092 in)

  29. If any of the cam lobe heights are less than the minimum, replace the camshaft.

  30. Object Number: 2017111  Size: SH
  31. Inspect the camshaft journals.
  32. Using a micrometer, measure the journal diameter.
  33. If the journal diameter is not as specified, check the oil clearance.