GM Service Manual Online
For 1990-2009 cars only

Tools Required

SA9179NE Dial Indicator


    Object Number: 1345871  Size: SH
  1. Inspect the 2nd clutch piston (746) and the clutch piston check valve.
  2. If the 2nd clutch check valve is missing, stuck or damaged, replace the complete 2nd clutch piston assembly.

    If the 2nd clutch piston spring washer (753) is not staked to the piston, replace the complete 2nd clutch piston assembly.


    Object Number: 1345451  Size: SH
  3. Inspect the following components:
  4. • 2nd clutch piston retaining ring (743)
    • 2nd clutch piston retainer cap (744)
    • 2nd clutch piston spring (745)

    Object Number: 1712528  Size: SH
  5. Inspect the following components for wear, damage, or discoloration:
  6. • 2nd clutch steel flat plates (742)
    • 2nd clutch fiber plates (741)
    • 2nd clutch selective backing plate (740)
    • 2nd clutch steel wave plates (760)
  7. If the 2nd clutch fiber plates (741) are worn or damaged, replace as a set.
  8. If the 2nd clutch steel flat plates (742) or the 2nd clutch steel wave plates (760) are worn, damaged, or severely discolored, replace the plates as a set.
  9. If the 2nd clutch selective backing plate (740) is worn, damaged, or severely discolored, inspect the 2nd clutch selective backing plate-to-top disc clearance, then replace the selective clutch backing plate as needed.

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.