GM Service Manual Online
For 1990-2009 cars only

Disassembly Procedure

Tools Required

J 23327 Clutch Spring Compressor


    Object Number: 143379  Size: SH
  1. Using a feeler gage (1) measure the first-reverse brake clearance between the number 2 inner one-way clutch race snap ring (7041) and the first-reverse brake flange snap ring (7042). If the clearance is greater than 0.58-1.92 mm (0.023-0.075 in), replace the first-reverse discs and plates.

  2. Object Number: 143310  Size: SH
  3. Remove the number 2 inner one-way clutch race snap ring (7041), being careful not to damage the inside of the transaxle case.

  4. Object Number: 143311  Size: SH
  5. Remove the eight first-reverse brake discs and plates (7043, 7044), starting with the first-reverse brake flange (7042).
  6. Remove the first-reverse brake damper plate (7045).
  7. Inspect all discs and plates for discoloration or abnormal wear.

  8. Object Number: 428182  Size: SH
  9. Install a J 23327 and J 37284 on the first-reverse brake return spring assembly inside of the transaxle case. Tighten the tool until you are able to remove the first-reverse brake return spring snap ring (7046). This will release the first-reverse brake return spring assembly (7047).

  10. Object Number: 143325  Size: SH
  11. Remove the first-reverse brake return spring assembly (7047), exposing the first-reverse brake piston (7049).

  12. Object Number: 143375  Size: SH
  13. Remove the piston (7049) from the transaxle case.
  14. Remove the piston seals (inner and outer) from the piston (7049).

  15. Object Number: 143329  Size: SH
  16. In order to remove the first-reverse brake piston, slowly apply low pressure compressed air into the first-reverse brake fluid pressure passage, identified in the illustration by the number 1.

Assembly Procedure

Tools Required

    • J 23327 Clutch Spring Compressor
    • J 36850 Transjel® Lubricant

    Object Number: 143375  Size: SH
  1. Inspect the first-reverse brake piston (7049) for the following conditions:
  2. • Porosity or damage
    • Ring groove damage
  3. Install the inner and outer piston seals onto the piston (7049). Lubricate the inner and outer piston seals with J 36850 .
  4. Install the piston (7049) into the transaxle case.

  5. Object Number: 143325  Size: SH
  6. Install the first-reverse brake return spring assembly (7047) onto the first-reverse brake piston (7049), with the spring side of the assembly facing toward the piston.

  7. Object Number: 143313  Size: SH
  8. Install a J 23327 over the spring assembly.
  9. Compress the spring assembly past the ring groove in the case hub. Do not compress the return spring assembly (7047) more than is necessary in order to fit the return spring snap ring (7046) into place.
  10. Install the return spring assembly snap ring (7046) into the case hub ring groove.

  11. Object Number: 143377  Size: SH

    Notice: Whenever you install new clutch discs in the firsts-reverse brake, the forward clutch or the direct clutch assemblies, you must first soak these discs for two hours in Dexron®-III automatic transmission fluid GM P/N 12341643, or equivalent. This causes the clutch material on the discs to permeate with the fluid. This will aid in ease of assembly and prevent clutch overheating on first time engagement.

  12. Install the first-reverse brake damper plate (7045) into the case. Place the convex side of the damper plate facing upward or away from the return spring assembly.

  13. Object Number: 143311  Size: SH
  14. Install four first-reverse brake plates (7043) and four brake discs (7044) into the case in an alternating sequence, beginning with a first reverse brake plate (7043).
  15. Install the first-reverse brake flange (7042). Place the flat side of the flange facing downward, against the last clutch disc.
  16. Install the number 2 one-way clutch race snap ring.

  17. Object Number: 143379  Size: SH
  18. Using a feeler gage, identified in the illustration by the number 1, measure the first-reverse brake clearance between the number 2 inner one-way clutch race snap ring and the first-reverse brake flange. If clearance is greater than 0.58-1.92 mm (0.023-0.075 in), replace the first-reverse discs and plates.

  19. Object Number: 143329  Size: SH
  20. Inspect the first-reverse brake piston for operation by slowly applying low pressure compressed air into the fluid passage marked in the illustration by the number 1. When you release the air pressure, the return spring assembly should force the piston back into its original position.