GM Service Manual Online
For 1990-2009 cars only

    Important: In order to maintain the proper component balance, contact surface taper and heat transfer, manual transmission flywheels are NOT to be machined.


    Object Number: 188129  Size: SH

    Caution: Wear safety glasses in order to avoid eye damage.

  1. Clean the engine flywheel (1 or 2) in cleaning solvent.
  2. Dry the engine flywheel with compressed air.

  3. Object Number: 381965  Size: SH

    Important: Do not attempt to repair the welded areas, if present, that retain the ring gear to the engine flywheel plate. Always install a NEW engine flywheel.

  4. Inspect the engine flywheel, automatic transmission, if equipped, for the following:
  5. • Stress cracks around the engine flywheel-to-torque converter bolt hole locations (1)
    • Missing balance weights
    • Stress cracks around the engine flywheel-to-crankshaft bolt hole locations (2 or 3)
    • Welded areas that retain the ring gear onto the engine flywheel for cracking (4), if present
    • Damaged ring gear teeth (5)

    Object Number: 64126  Size: SH
  6. Inspect the engine flywheel, manual transmission, if equipped, for loose or improperly installed flywheel weights, if applicable.
  7. A properly installed flywheel weight should be installed until flush or below flush with the face of the engine flywheel.


    Object Number: 188086  Size: SH
  8. Inspect the engine flywheel, manual transmission, if equipped, for the following:
  9. • Pitted friction surface (1)
    • Scoring or grooves (2)
    • Rust or other surface damage (3)
    • Damaged ring gear teeth (4)
    • Loose or improperly positioned ring gear
    • The ring gear has an interference fit onto the engine flywheel and the ring gear should be positioned completely flat against the flange of the engine flywheel.