GM Service Manual Online
For 1990-2009 cars only

    Object Number: 64123  Size: SH

    Important: 

       • Note the position and direction of the engine flywheel before removal. The flywheel does not use a locating pin for alignment. Mark or scribe the end of the crankshaft and the flywheel before component removal. The existing manual transmission engine flywheel must be installed to the original position and direction. The engine flywheel will not initially seat against the crankshaft flange, but will be pulled onto the crankshaft by the engine flywheel bolts. This procedure requires a three stage tightening process.
       • DO NOT remove the propshaft hub or flexplate from the automatic transmission engine flywheel. The flywheel, propshaft hub, and flexplate are balanced as an assembly. If service is required, the entire flywheel assembly should be replaced.

  1. Remove the engine flywheel bolts.
  2. Remove the automatic transmission engine flywheel, if applicable.

  3. Object Number: 506140  Size: SH
  4. Mark or scribe the end of the crankshaft and the manual transmission flywheel. Refer to Engine Balancing .

  5. Object Number: 156166  Size: SH
  6. Remove the manual transmission engine flywheel, if applicable.

  7. Object Number: 188086  Size: SH
  8. Clean the flywheel in solvent.
  9. Caution: Wear safety glasses in order to avoid eye damage.

  10. Dry the components with compressed air.
  11. Inspect the manual transmission flywheel for loose or improperly installed balance weights.
  12. A properly installed balance weight should be installed until flush or below flush with the face of the flywheel.

  13. Inspect the manual transmission flywheel for the following:
  14. • Pitted surfaces (1)
    • Scored or grooved surfaces (2)
    • Rusted surface (3)
    • Damaged ring gear teeth (4)
    • Missing, bent, or damaged pressure plate locating pins
    • The two locating pins are installed into the flywheel and spaced 180 degrees apart.
  15. Inspect the automatic transmission flywheel for the following:
  16. • Damaged ring gear teeth
    • Stress cracks around the flywheel-to-crankshaft bolt hole locations

       Important: Do not attempt to repair the welded areas that retain the ring gear to the flywheel plate. Install a new flywheel.

    • Welded areas that retain the ring gear to the flywheel for cracking