GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1996 🢒 Chevy MD Steel Tilt (W Model) 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 4L80-E 🢒 Center Support and Gear Unit Assembly Assemble

Tools Required

    • J 6116-A Gear Unit Holding Fixture
    • J 36850 TRANSJEL™

    Object Number: 28719 Size: SH
  1. Assemble the main shaft (662) into the rear internal gear (666).
  2. Install the main shaft retaining ring (670) onto the main shaft.

    3. Object Number: 28720 Size: SH
  3. Assemble the sun gear rear thrust bearing (664) and races (663 & 665) onto the main shaft (662).
  4. The lips on the sun gear thrust bearing races should face the thrust bearing.
  5. Retain the thrust bearing and races with J 36850 or equivalent.

    6. Object Number: 28722 Size: SH
  6. Lubricate the output carrier pinion gears (655) with DEXRON®III transmission fluid.
  7. Assemble the main shaft and rear internal gear assembly (666) into the output carrier assembly (661).
  8. Place the assembly into J 6116-A with the main shaft facing down.

    9. Object Number: 28724 Size: SH
  9. Assemble the rear internal gear thrust bearing (647) and races (648 & 669). The lips of the sun gear thrust bearing races should face the thrust bearing.
  10. Place the bearing and race assembly onto the rear internal gear hub. Retain with J 36850 or equivalent.

    11. Object Number: 28725 Size: SH
  11. Assemble the output shaft (671) into the output carrier assembly (661).
  12. Install the output shaft retaining ring (672).
  13. Assemble the output shaft selective thrust washer (673) (plastic) to the output shaft.
  14. Refer to the end play measurement taken during disassembly. Refer also to the Output Shaft Selective Thrust Washer Chart found in End Play Specifications in order to select the proper thrust washer.
  15. Retain the thrust washer with J 36850 or equivalent.
  16. Align the thrust washer tabs with the pockets in the carrier.

    17. Object Number: 28727 Size: SH
  17. Turn the gear unit assembly over and place it into J 6116-A with the output shaft (671) facing down.
  18. Install the front internal reaction carrier thrust washer (659) into the output carrier assembly.
  19. Lubricate the reaction drum carrier pinion gears with DEXRON™III transmission fluid.
  20. Assemble the reaction drum and carrier assembly (651) into the output carrier assembly (661).
  21. Rotate the reaction drum and carrier assembly to ease assembly.

    22. Object Number: 28728 Size: SH
  22. Assemble the sun gear (650) into the reaction drum and carrier assembly (651).
    23. • Insert the chamfered inner diameter first
    • Rotate the sun gear to ease assembly
  23. Assemble the sun gear shaft (649) with the long splined end into the sun gear.

    24. Object Number: 28730 Size: SH
  24. Assemble the longer lipped center support thrust bearing race (648) onto the sun gear shaft (649) with the lip facing upward.
  25. Assemble the center support thrust bearing (647) onto the bearing race (648).

    26. Object Number: 28731 Size: SH
  26. Assemble the thrust bearing race (646) to the rear hub of the center support (640). Retain the thrust bearing race with J 36850 or equivalent.
  27. Assemble the reaction carrier thrust washer (642) (brass) into the recess of the center support. Retain the thrust washer with J 36850 or equivalent.

    28. Object Number: 28733 Size: SH
  28. Install a new center support (640) or the reconditioned center support into the reaction carrier (651).
  29. Verify correct assembly by holding the reaction carrier drum stationary and by rotating the center support. The center support should only turn counterclockwise.