GM Service Manual Online
For 1990-2009 cars only

Tools Required

SA9179NE Dial Indicator


    Object Number: 1470589  Size: SH
  1. Clean the clutch components, except the clutch fiber plates in solvent and air dry.
  2. Inspect the clutch piston check valve in the clutch pistons for looseness or damage.
  3. Inspect the O-ring seal groove in the clutch pistons for nicks, scratches, or burrs.
  4. Inspect for excessively worn or bent piston retainer caps.
  5. Inspect the clutch piston return springs for the correct free length. Refer to Transmission Clearance Specifications , Clutch Return Spring Free Length.
  6. Inspect the 4th and 5th/reverse clutch hub for worn grooves in the clutch plate notches that will prevent the clutch plates from sliding.
  7. Inspect the clutch steel plates for heat damage, excessive wear, or warping.
  8. Inspect the clutch fiber plates for heat damage, wear, and discoloration.
  9. Inspect the clutch backing plate for heat damage and excessive wear.
  10. Replace all faulty clutch components. Replace the clutch plates as a set.

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.