GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 8001 Dial Indicator Set
    • J 21465-13 Drive Handle Extension
    • J 36996 Balance Shaft Installer
    • J 45059 Angle Meter

    Object Number: 566836  Size: SH
  1. Use J 21465-13 and J 36996 to install the balance shaft into the engine block.

  2. Object Number: 42237  Size: SH
  3. Install the balance shaft retainer.
  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 balance shaft retainer bolts.
  6. Tighten
    Tighten the balance shaft retainer bolts to 30 N·m (22 lb ft).


    Object Number: 154521  Size: SH
  7. Install the balance shaft driven gear.
  8. Notice: This bolt is designed to permanently stretch when tightened, and therefore MUST be replaced anytime it is removed. The correct part number fastener must be used to replace this type of fastener. Do not use a bolt that is stronger in this application. If the correct bolt is not used, the parts will not be tightened correctly. The system or the components may be damaged.

  9. Install the balance shaft driven gear bolt.
  10. Tighten
    Tighten the balance shaft driven gear bolt to 22 N·m (16 lb ft). Use J 45059 to tighten the bolt an additional 70 degrees.


    Object Number: 38470  Size: SH
  11. Using J 8001 measure the balance shaft end play. End play must not exceed 0.028 mm (0.008 in).

  12. Object Number: 38472  Size: SH
  13. Using J 8001 measure the balance shaft radial play at the rear. Radial play must be between 0.0127-0.119 mm (0.0005-0.0047 in).
  14. Install the balance shaft drive gear.
  15. Install the camshaft sprocket.
  16. Turn the camshaft so the timing mark on the camshaft sprocket is straight down.
  17. Remove the camshaft sprocket and balance shaft drive gear.
  18. Turn the balance shaft so the timing mark on the balance shaft driven gear points straight down.
  19. Partially install the balance shaft drive gear so the gear teeth are not engaged.
  20. Align the marks on the balance shaft driven gear and the balance shaft drive gear. Do this by turning the balance shaft.
  21. Once marks are aligned, fully seat balance shaft drive gear and engage gear teeth.
  22. Turn the crankshaft so the number one piston is at top dead center.
  23. Install the timing chain and camshaft sprocket.

  24. Object Number: 38477  Size: SH
  25. Using J 8001 measure the gear lash at four places. Measure every quarter turn. Gear lash must be between 0.050-0.127 mm (0.002-0.005 in).