Disassembly
Transmission
All vehicles
NOTE: For additional information, refer to the exploded view under the Assembly procedure.
1. Clean the transmission exterior with solvent and dry with compressed air.
2. Remove the clutch release lever and the clutch release hub and bearing.
3. NOTE: For vehicles equipped with gasoline engines, the transmission must be elevated 50-101 mm (1.968-3.976 in) to prevent damage to the input shaft.
Position the transmission on the floor with the output flange pointing upward.
Rear Wheel Drive (RWD) vehicles
4. Using the Drive Pinion Flange Holding Fixture and the Mainshaft Locknut (36-mm) Socket, remove the pinion flange.
All vehicles
5. Remove the 19 extension housing bolts.
6. NOTE: Use a 1/8-in center punch to create a pilot hole in the plug before installing the tool. Using the Jet Plug Remover to make the pilot hole will damage the tool.
NOTE: Lightly thread in the Jet Plug Remover so as not to damage the springs.
Using the Jet Plug Remover, remove the detent plugs and shift detent springs. Discard the detent plugs.
7. Remove the main shift detent.
8. Separate the main shift detent from the detent plunger.
- Inspect the detent plunger for wear or damage. Install a new dent plunger as necessary.
9. Remove the extension housing from the intermediate housing.
- Using a soft-faced hammer, tap the extension housing lightly to break the gasket seal.
10. Remove the intermediate housing-to-case bolts.
11. Using a suitable lifting device, a suitable chain and 2 S-hooks, lift the intermediate housing and gear assembly out of the main case.
- Place the S-hooks in the intermediate housing where the 2 bolts were removed.
- Place a protective cover or rag around the chain. This will make sure the low and reverse gears are not damaged during removal.
- Lift the transmission 25 mm (0.984 in) off the ground. Using a soft-faced hammer, lightly tap the main housing to break the gasket seal.
12. Position the intermediate housing and gear assembly on the Gear Pack Fixture.
- Securely fasten the holding plate to a sturdy work bench.
13. Remove the 2 roll pins and the low/reverse/5th gear main shift rail driver.
- Use a hammer and punch or an air hammer and roll pin remover.
14. NOTE: The shift finger is also the 1st/2nd and 3rd/4th rail driver.
Remove the lower roll pins.
- Use a hammer and punch or an air hammer and roll pin remover to remove.
- For vehicles equipped with a diesel engine, the shift finger is short. For vehicles equipped with a gas engine, the shift finger is long.
15. Remove the lower shift finger and the main shift rail.
1. Remove the lower shift finger.
- Rotate the rail driver counterclockwise and pull outward to remove.
2. Remove the main shift rail.
16. Align the interlock plate into 2nd gear position, engage 2nd gear, then remove the two 5th gear shift fork roll pins.
- Use a hammer and punch or an air hammer and roll pin remover to remove.
- Discard the roll pins.
17. Remove the 5th gear shift fork and shift rail.
- Align the interlock plate into the 5th gear position. Remove the shift rail by tapping the shift fork with a soft-faced hammer while pulling up on the shift rail.
18. Remove the 2 low/reverse gear shift fork roll pins.
- Use a hammer and punch or an air hammer and roll pin remover to remove.
- Discard the roll pins.
19. NOTE: Make sure the interlock plate is in the low/reverse gear position before removing. Shift the transmission into low gear.
Remove the low/reverse gear shift fork and shift rail.
- Align the interlock plate into the low/reverse gear position. Remove the shift rail by tapping the shift fork with a soft-faced hammer while pulling up on the shift rail and fork.
20. NOTE: The shift rail detents can be difficult to remove. Using a heat gun, apply heat to the intermediate plate to ease removal.
Remove the shift rail detents, if necessary.
21. On Four-Wheel Drive (4WD) vehicles, remove and discard the snap ring.
22. Using the Shaft Protector Set and the 2 or 3 Jaw Puller, remove the mainshaft rear bearing, the output bearing thrust washer, mainshaft low gear, the mainshaft low gear bushing, the synchronizer assembly (low and reverse) and the mainshaft reverse gear.
23. Remove the mainshaft rear bearing and the output bearing thrust washer from the low and reverse assembly.
- Inspect the bearing for wear or damage. Install a new bearing as necessary.
- Always install new bearings and cups as a set.
24. Remove the mainshaft needle bearings.
- Inspect the bearings for wear or damage. Install new bearings as necessary.
25. Remove the low gear from the low and reverse synchronizer assembly.
- Inspect the low and reverse gears for wear or damage. Install new gears as necessary.
26. Disassemble the low and reverse synchronizer assembly.
- Inspect the components for wear or damage. Inspect the internal surface of the synchronizer rings for a contact pattern. The contact pattern should be the same on the entire internal circumference of the ring.
27. Check the clearance between the synchronizer ring and the gear.
1. Place the synchronizer ring onto the synchronizer sliding sleeve. Position the synchronizer ring on the gear.
2. Insert a feeler gauge and measure the clearance, while applying pressure and rotating the synchronizer ring. The clearance should be the same around the entire circumference.
- Place the feeler gauge between the ring and gear. The ring has a raised section, inserting the feeler gauge past the teeth will give a incorrect reading.
- If the clearance is less than 1.0 mm (0.039 in) for low or reverse gear, install a new synchronizer assembly, low gear or reverse gear to obtain correct specification.
28. Remove the mainshaft needle bearing.
29. For vehicles equipped with a diesel engine, remove the low gear thrust washer.
30. Remove and discard the snap ring.
- This is a selective fit snap ring.
31. Remove the countershaft rear thrust washer.
32. Remove the 5th gear.
33. Remove the countershaft needle bearing.
34. Remove the interlock plate bolts.
35. NOTE: Do not use power tools to remove.
NOTE: Make sure the shift rails are not binding while pulling up on the intermediate housing.
Using the Shaft Protector Set and Front Wheel Hub Remover/Installer with Centerplate Legs, remove the countershaft bushing, the countershaft 5th gear synchronizer assembly and the intermediate housing.
- When installing the Centerplate Legs, position them opposing one another.
- Inspect the countershaft 5th gear synchronizer, countershaft bushing and the intermediate plate for wear or damage. Install new components as necessary.
36. Disassemble the countershaft 5th gear synchronizer assembly.
- Inspect the components for wear or damage. Inspect the internal surface of the synchronizer ring for a contact pattern. The contact pattern should be the same on the entire internal circumference of the ring.
37. Check the clearance between the synchronizer ring and the gear.
1. Place the synchronizer ring onto the synchronizer sliding sleeve. Position the synchronizer ring on the gear.
2. Insert a feeler gauge and measure the clearance, while applying pressure and rotating the synchronizer ring. The clearance should be the same around the entire circumference.
- Place the feeler gauge between the ring and gear. The ring has a raised section. Inserting the feeler gauge past the teeth will give an incorrect reading.
- If the clearance is less than 1.0 mm (0.039 in) for 5th gear, install a new synchronizer assembly or 5th gear to obtain correct specification.
38. NOTICE: To prevent damage, do not heat the mainshaft rear bearing, the countershaft or mainshaft rear thrust washer, the mainshaft bushing or the countershaft bushing higher than 150°C (302°F) maximum.
NOTE: Make sure the components are heated to 150°C (302°F) for reassembly.
New or original components should be heated in advance of the assembly procedure. Heating will ease the assembly process. Place the mainshaft rear bearing, the countershaft rear thrust washer, the countershaft bushing, the rear mainshaft bearing and the mainshaft low gear bushing into the Gear/Bearing Heater.
39. Remove the interlock plate, the 1st/2nd and 3rd/4th shift fork and shift rail assemblies.
40. Inspect all the shift fork pads and centers for wear or damage. Install new shift forks as necessary.
41. NOTICE: To prevent damage, do not heat the bearings higher than 150°C (302°F) maximum.
Inspect the mainshaft middle bearing, the countershaft middle bearing and the bearing cups in the intermediate housing for wear or damage. Install new components as necessary.
- Always install new bearings and cups as a set.
- The bearings should be heated to install. Place the bearings in the Gear/Bearing Heater.
42. Remove the countershaft rear bearing spacer.
43. Remove the countershaft from the Gear Pack Fixture and set it aside.
