GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

J 34673 Flat Gage Bar

  1. Remove the 16 upper valve body bolts.
  2. Important: The upper half of the valve body contains 4 steel check balls, also known as check halves. When you seperate the valve body halves, do so with the upper half facing downward in order not to displace the 4 check balls. When you reassemble the valve body, confirm that you have positioned these check balls in their correct passages. Failure to observe this procedure may result in transaxle shift failure. When disassembly the valve body halves, keep all valve springs, spring seats and plugs within their respective valves. Most springs are different in sizes and CANNOT be interchanged. Verify that all parts are clean and dry before assembly.

  3. Dissassemble the lower valve body from the upper valve body. Position the upper valve body on bottom and the lower on the top.
  4. Remove the spacer plate and the gaskets.

  5. Object Number: 179563  Size: LH
  6. Remove the 4 check balls from the upper valve body. Refer to Valve Body and Accumulators
  7. Remove the neutral drain nozzle (19) from the upper valve body.
  8. Remove the manual valve (20) from the upper valve body.
  9. Remove the No. 3 valve body key (2) from the upper valve body.
  10. Remove the pressure regulator valve sleeve (1) from the upper valve body.
  11. Remove the primary regulator valve plunger (3) from the upper valve body.
  12. Remove the plate washer (4) from the upper valve body.
  13. Remove the primary regulator valve spring (5) from the upper valve body.
  14. Remove the primary regulator valve (6) from the upper valve body.
  15. Remove the following components from the upper valve body:
  16. • The throttle valve cam bolt (13)
    • The cam (16)
    • The bushing (17)
    • The spring (18)
  17. Remove the downshift plug (12) from the upper valve body.
  18. Remove the No. 2 throttle valve spring (11) from the upper valve body.
  19. Remove the E-clip retainer (9) from the throttle valve in the upper valve body.
  20. Remove the throttle valve spring (10) from the upper valve body.
  21. Remove the No. 1 throttle valve (8) from the upper valve body.
  22. Clean all parts with clean solvent and dry them thoroughly.
  23. Inspect the upper valve body for distorted or damaged valve bores.
  24. Inspect the upper valve body for blocked fluid passages.
  25. Place J 34673 across the upper valve body mating surface.
  26. Rotate J 34673 . Inspect for surface warp every 30 degrees.
  27. If upper valve body surface warp exists, replace the upper valve body.

  28. Inspect all of the valves, springs, and attaching parts for unusual wear or damage. Replace as necessary.

Installation Procedure

Tools Required

J 36850 Transjel® Transmission Assembly Lubricant


    Object Number: 179563  Size: LH
  1. Apply a thin coat of J 36850 to all parts prior to assembly.
  2. Install the No. 1 throttle valve (8) into the upper valve body (7).
  3. Install the throttle valve spring (10) into the upper valve body.
  4. Install the E-clip retainer (9) onto the throttle valve in the upper valve body.
  5. Install the No. 2 throttle valve spring (11) into the upper valve body.
  6. Install the downshift plug (12) into the upper valve body.
  7. Install the following components into the upper valve body:
  8. • The throttle valve cam bolt (13)
    • The cam (16)
    • The bushing (17)
    • The spring (18)
  9. Install the primary regulator valve (6) into the upper valve body.
  10. Install the primary regulator valve spring (5) into the upper valve body.
  11. Install the plate washer (4) into the upper valve body.
  12. Install the primary regulator valve plunger (3) into the upper valve body.
  13. Install the pressure regulator valve sleeve (1) into the upper valve body.
  14. Install the No. 3 valve body key (2) into the upper valve body.
  15. Install the manual valve (20) into the upper valve body.
  16. Install the neutral drain nozzle (19) into the upper valve body.

  17. Object Number: 179564  Size: SH
  18. Install four check balls (2) into the upper valve body.
  19. Inspect all of the valves in order to ensure smooth operation.
  20. Install the gaskets and the spacer plate.
  21. Position the upper valve body with the lower valve body.
  22. Install the 16 valve body bolts. Refer to Valve Body and Accumulators
  23. Install the valve body assembly to the transmission. Refer to Valve Body and Accumulators