GM Service Manual Online
For 1990-2009 cars only

    Object Number: 412472  Size: SH
  1. Inspect the balance shaft drive chain guides for cracking or wear.
  2. Replace the balance shaft drive chain guides if wear exceeds 1.12 mm (0.045 in) depth on the chain guide surface.
  3. Inspect the balance shaft drive chain tensioner guide shoe for wear.
  4. Replace the balance shaft drive chain tensioner guide shoe if wear exceeds 1.12 mm (0.045 in) depth on the chain guide surface.

  5. Inspect the balance shaft drive chain and sprockets for wear.
  6. Important: The crankshaft sprocket is not serviceable.

  7. Inspect the crankshaft sprocket faces for signs of movement.
  8. Inspect the alignment notch in the balance shaft for cracking or damage.
  9. Inspect the water pump, crankshaft, and balance shaft sprocket teeth and chain for signs of excessive wear, chipping, or seizure of the balance shaft drive chain links.
  10. Inspect the timing chain tensioner for damage or wear.