GM Service Manual Online
For 1990-2009 cars only
  1. With the manual selector in P (park) position, start engine.
  2. With engine at idle, note any abnormal vibration.
  3. Move the manual selector to N (neutral) position and note any abnormal vibration.
  4. Return the manual selector to P (park) position and turn ignition switch to the LOCK position.
  5. Raise and suitably support the vehicle.
  6. Remove the flywheel cover.
  7. Remove the flywheel-to-torque converter bolts.
  8. Rotate torque converter 120 degrees (1/3 turn).
  9. 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.

  10. Install the flywheel-to-torque converter bolts.
  11. Tighten
    Flywheel-to-torque converter bolts to 19 N·m (14 lb ft).

  12. Install flywheel cover.
  13. Lower vehicle.
  14. With the manual selector in P (park) position, start the engine.
  15. If any abnormal vibration still exists, repeat this procedure until the best possible balance is obtained.