GM Service Manual Online
For 1990-2009 cars only

Tools Required

SA9179NE Dial Indicator


    Object Number: 1353670  Size: SH
  1. Inspect the 3rd clutch piston (818) and the clutch piston check valve.
  2. Replace the 3rd clutch piston if the check valve is missing, stuck, or damaged.

  3. Object Number: 1345576  Size: SH
  4. Inspect the following components for wear or damage:
  5. • 3rd clutch piston spring cap (815)
    • 3rd clutch piston retaining ring (814)
    • 3rd clutch piston return spring (816)
  6. Replace the components if faulty.

  7. Object Number: 1712529  Size: SH
  8. Inspect the following 3rd clutch components for wear, damage, or severe discoloration:
  9. • 3rd clutch steel flat plates (813)
    • 3rd clutch steel wave plates (830)
    • 3rd clutch fiber plates (812)
    • 3rd clutch selective backing plate (811)
  10. If the clutch steel plates are worn or damaged or severely discolored, replace the plates as a complete set.
  11. If the clutch fiber plates are worn, damaged, or discolored, replace the plates as a complete set.
  12. If the 3rd clutch selective backing plate (811) is worn, damaged, or severely discolored, inspect the clutch backing plate-to-top disc clearance, then replace the clutch backing plate making sure to use the correct selective size backing plate.

Clutch Wave Plate Phase Difference Inspection


    Object Number: 1714683  Size: SH
  1. Place the clutch wave plate on a surface plate, and set SA9179NE on the wave plate.
  2. Find the bottom (D) of a phase difference of the wave plate, zero the SA9179NE and make a reference mark on the bottom of the wave plate.
  3. Rotate the clutch wave plate of the clutch about 60-degrees apart from the bottom while holding the wave plate by the circumference. The SA9179NE should be at the top (E) of a phase difference. Do not rotate the wave plate while holding the surface, always rotate the plate by holding the circumference.
  4. Read the SA9179NE . The SA9179NE reads the phase difference (C) of the wave plate between the bottom and top.
  5. Specification
    Standard: 0.05 mm (0.002 in) minimum

  6. Rotate the wave plate of the clutch about 60-degrees. The SA9179NE should be at the bottom of a phase difference (F and H), and zero the SA9179NE .
  7. Measure the phase difference at the other 2 tops (G and I) of the wave plate by following steps 3 through 5.
  8. If the 2 values of the 3 measurements are within the standard, the wave plate is OK. If the 2 values of the 3 measurements are out of the standard, replace the wave plate.