Assembly
Input Shift Bearing Retainer AssemblyInstallation Procedure
Tools Required
J 38807 Main Drive Gear Bearing Retainer Seal Installer
Install the oil seal into the main drive gear bearing retainer. The lip of the seal goes toward the installing tool. Use the J 38807.
Rear Housing Disassembly
Tools Required
- Hydraulic Press
- J 23907 Slide Hammer with Pilot Bearing Puller
1. Remove the rear housing shift shaft bearing. Use tool J 23907 with a suitable pilot bearing puller.
- Install the puller legs behind the bearing lip.
- If the bearing lip breaks OFF, install the puller legs behind the inside (outer end) bearing lip.
2. Drive out 2 dowel pins.
3. Remove the following components:
1. 3 bolts
2. The output shaft bearing retainer
4. Remove the output shaft bearing assembly. Use a brass drift.
5. Remove the gasket material from the housing. Use liquid gasket remover.
Front Housing Assembly
Tools Required
- Hydraulic Press
- J 36183 Input Shaft Press Tube with Cap
- J 36184 Adapter Press Tube Reducer
- J 36510 Clutch Fork Pivot Remover/Installer
- J 36507 Detent Bushing Remover/Installer
- J 36511 Oil Fill Plug Hex Bit (17 mm)
- J 36798 Shift Shaft Bushing Installing Tool
- J 36190 Diver Handle
1. Install the input shaft bearing.
- Press in the bearing until the snap ring is seated.
- Use J36183 and J36184.
- Use a hydraulic press.
2. Install the shift shaft front housing bushings. Use J 36798 and J 36190.
3. Install the clutch fork pivot assembly. Use J 36510 and J 36190.
4. Install the two detent plunger bushings. Use J 36507.
5. Install the first bushing until the second scribe mark on the tool aligns with the housing.
6. Install the second bushing until the first scribe mark on the tool aligns with the housing.
7. Install the transmission housing vent assembly.
8. Apply pipe sealant with Teflon (TM) GM P/N 1052080 or equivalent on the fill plug threads.
9. Install the oil fill plug. Use J 36511.
Tighten
Tighten the fill plug to 60 N.m (44 lb ft).
10. Apply pipe sealant with Teflon GM P/N 1052080 or equivalent to the drain plug threads.
11. Install the oil drain plug. Use tool J 36511.
Tighten
Tighten the drain plug to 60 N.m (44 lb ft).
Reverse Idler Gear Assembly
1. Lubricate all the parts as the assembly progresses. Use Synchromesh Transmission Fluid GM P/N 12345349 or equivalent.
2. Install the snap ring.
3. Install the wave washer.
4. Install the locating ball.
5. Install the thrust washer.
6. Install the bearing assembly.
7. Install the reverse idler gear.
8. Install the locating ball.
9. Install the thrust washer.
10. Install the snap ring.
Transmission Assembly
Tools Required
- J 3289-20 Base Holding Fixture
- J 8763-02 Holding Fixture C-Clamp
- J 8763-21 Balance Bracket for C-Clamp
- J 36502 4WD Oil Seal Installer
- J 36502-2A 4WD Seal Protector
- J 36515 Assembly Pallet
- J 36515-10 Retainer Alignment Cable (2WD Models Only)
- J 36515-15 Mainshaft Adapter
- J 36515-16 Countershaft Adapter
- J 36824 Transmission Adapters
Important: Some parts require an assembly lubricant. Use TRANSJEL or equivalent.
1. Install the pilot bearing into the input shaft.
- Turn the small diameter of the bearing cage toward the input shaft. Retain the bearing with TRANSJEL or equivalent.
2. Install the following parts on the assembly fixture J 36515-15 and J 36515.
1. The input shaft
2. The pilot bearing
3. The synchronizer ring
4. The mainshaft assembly
3. Install the following parts on the mainshaft and on the assembly fixture tool J 36515-16.
1. The countershaft assembly (1)
2. The reverse idler assembly (2)
3. The 1st/2nd speed gear shift fork (3)
4. The 5th/Reverse speed gear shift fork (4)
4. Apply TRANSJEL or equivalent to the countershaft bearing.
Important: Press each bearing roller towards the countershaft race. This will secure them for easier assembly.
5. Install the countershaft bearing on the countershaft. Use TRANSJEL or equivalent in order to retain the bearing. The smaller diameter of the bearing cage goes into the bearing race of the housing.
Important: Bring the housing straight down. If you feel resistance at about 7 mm (1/4 in), then the counter shaft bearing rollers are cocked. Repeat the procedure. Do not force the housing down.
6. Install the rear housing assembly.
1. Make sure the reverse idler shaft is lined up with the hole in the case.
2. Rotate the housing back and forth while pulling down.
7. Install a new output shaft bearing snap ring.
8. Install the seal protector tool J 36502-2A on the output shaft.
9. Install the rear housing main shaft oil seal. Use J 36502.
10. Remove the seal protector J 36502-2A.
11. Fill the space between the seat lip with chassis grease. Use GM P/N 1052497 or equivalent.
12. Lay the rear housing assembly down on the workbench. Remove J 36515, J 36515-15, and J 36515-16 from the housing.
13. Apply pipe sealant with Teflon GM P/N 1052080 or equivalent to the bolt hole.
14. Apply thread locker GM P/N 12345382 or equivalent to the bolt threads.
15. Install the following components:
1. The idler shaft support
2. The idler shaft bolts
3. Line up the bolt threads in the idler shaft support with the bolt hole.
4. Hold the reverse idler shaft against the idler support while tightening the bolts.
Tighten
Tighten the bolts to 22 N.m (16 lb ft).
16. Install J 8763-21, J 8763-02, and J 36824 on the transmission housing.
17. Install the 3rd/4th sped gear shift fork onto the 3rd/4th speed gear synchronizer sleeve. Align all three insert notches.
18. Assemble the following parts onto the shift shaft:
1. The 3rd/4th speed gear shift fork. Make the detent reliefs in the shift shaft point out.
2. The shift lever
3. The block-out bushing
4. The 1st/2nd speed gear shift fork
5. The shift socket
19. Slide the shift shaft all the way into the housing.
20. Install a new roll pin into shift lever.
1. Rotate the shift shaft and the shift lever/block-out bushing assembly. Make sure the roll pin holes are aligned and horizontal.
2. Support the shift shaft while installing the roll pin.
3. Install the roll pin flush with the shift lever.
21. Install the detent spring and the ball plunger into the hole in the shift lever.
1. Rotate the shift shaft counterclockwise. The shift lever should be almost into the 5th/Reverse speed gear insert notch.
2. Install the spring and the ball plunger into the shift lever.
3. Rotate the shift shaft until the shift lever aligns with the 3rd/4th speed gear insert.
Notice: Excessive force peens the shift shaft and damages the shift shaft bearing. This causes increased shift effort.
Important: Use the rear roll pin hole on the M50 transmission.
22. Install the shift socket roll pin.
1. Align the holes in the shift socket and the shift shaft.
2. Drive the roll pin flush with the bottom of the shift socket.
23. Apply gasket maker GM P/N 1052943 or equivalent to both sides of the isolator plate.
24. Install the isolator plate onto the housing.
The thin side of the plate should be on the left side of the transmission housing.
25. Install the shift lever.
26. Install the four bolts.
Tighten
Tighten the bolts to 8.5 N.m (75 lb in).
Important: The smaller diameter of the bearing cage goes into the bearing race.
27. Install the countershaft bearing in the front housing.
1. Apply TRANSJEL or equivalent on the bearing rollers.
2. Press each bearing roller into the cage.
3. Apply TRANSJEL or equivalent to the bearing race on the input shaft.
Important: Bring the housing straight down. If you feel resistance at about 7 mm (1/4 in), then the rollers are cocked. Repeat the procedure. Do not force down the housing.
28. Install the front housing.
29. Install the 2 housing dowel pins. Drive the dowel pins into the front housing flange.
30. Install the housing bolts.
- Do not tighten the bolts. Tip the transmission vertically.
31. Install a new snap ring on the input shaft.
You may need to pull out on the input shaft in order to install the snap ring.
Important: Do not allow the gasket maker material to plug the oil return hole. This reduces oil flow through the input shalt bearing. Premature bearing failure could result from a plugged oil return hole.
32. Apply gasket maker GM P/N 1052943 or equivalent to the inside edge of the bearing retainer bolt hole pattern.
33. Install the following components:
1. The input shaft bearing retainer assembly Align the oil drain back hole with the hole in the housing.
2. The 6 bolts.
Tighten
Tighten the bolts to 8.5 N.m (75 lb in)
34. Apply pipe sealant to the detent plunger plug. Use pipe sealant with Teflon TM GM P/N 1052080 or equivalent
35. Install the following components:
1. The shift shaft detent plunger
2. The shift shaft detent spring
3. The plug
Use a brass drift in order to install the plug.
36. Apply pipe sealant to the backup lamp switch threads. Use pipe sealant with Teflon TM GM P/N 1052080 or equivalent.
37. Install the backup lamp switch assembly.
Tighten
Tighten the switch to 9 N.m (80 lb in).
38. Remove J 8763-02 and J 36824.
39. Install 2 bottom housing bolts.
Tighten
Tighten the bolts to 35 N.m (26 lb ft).
40. Install the shift shaft block-out bushing pin.
Tighten
Tighten the bolt to 25 N.m (18 lb ft).
41. Fill the transmission with lubricant.
1. Refer to Manual Transmission Fluid; Specifications.
2. Use Synchromesh Transmission Fluid GM P/N 12345349 or equivalent.
3. Remove the oil fill plug. Use J 36511.
4. Install the transmission lubricant.
5. Install the oil fill plug.
Tighten
Tighten the oil fill plug to 60 N.m (44 lb ft).