Exploded View

1. Mainshaft front bearing outer race
2. Mainshaft front bearing inner race 3. Mainshaft
4. 1st main gear
5. 1st inner baulk ring 6. 1st synchronizer cone 7. 1st outer baulk ring 8. Spread spring
9. 1st-2nd synchronizer hub 10. 1st-2nd coupling sleeve 11. 2nd outer baulk ring 12. 2nd synchronizer cone 13. 2nd inner baulk ring 14. Mainshaft bushing
15. 2nd main gear
16. Thrust washer
17. 3rd main gear
18. 3rd baulk ring
19. 3rd-4th synchronizer hub 20. 3rd-4th coupling sleeve 21. Spring
22. Insert key
23. 4th baulk ring
24. 4th main gear
25. Adjusting shim
26. Mainshaft rear bearing inner race 27. Mainshaft rear bearing outer race 28. 5th main gear

: Apply gear oil.

: Apply Thread Locking Sealant,
Loctite Frenbloc or an equivalent.

: Replace the parts as a set.

: Always replace after every
disassembly.

: Select with proper thickness.

: N·m (kg-m, ft-lb)

Disassembly

CAUTION:
Place a direction mark on the surface of gears, avoiding an effect on their functions.

1. Set puller (A) at the area shown by (
) on the 3rd main gear (1).

: 3rd baulk ring side

2. Remove the 3rd main gear, using a press. The following parts become detached together at the same time: • Mainshaft bushing
• 3rd-4th synchronizer hub • 3rd baulk ring

CAUTION:
Never drop mainshaft.

3. Set puller (A) to 1st main gear (1).

4. Remove the 1st main gear, using a press. The following parts become detached together at the same time: • Mainshaft bushings
• Thrust washer
• 2nd main gear
• 2nd inner baulk ring
• 2nd synchronizer cone
• 2nd outer baulk ring
• 1st-2nd coupling sleeve • 1st-2nd synchronizer hub • 1st outer baulk ring
• 1st synchronizer cone
• 1st inner baulk ring

CAUTION:
Never drop mainshaft.

5. Remove spread springs from 1st-2nd synchronizer hub.

6. Remove mainshaft front bearing inner race, using a puller [Commercial service tool].

Assembly

CAUTION:
After replacing the following parts, adjust mainshaft rear bearing preload. Refer to TM-51, "Inspection and Adjustment".

• Mainshaft
• Mainshaft front bearing inner race • Mainshaft front bearing outer race • Mainshaft rear bearing inner race • Mainshaft rear bearing outer race • Clutch housing
• Transaxle case

1. Install 1st main gear to mainshaft.

2. Apply gear oil to 1st inner baulk ring, 1st synchronizer cone, and 1st outer baulk ring.

CAUTION:
Replace 1st inner baulk ring, 1st synchronizer cone, and 1st outer baulk ring as a set.

3. Install 1st inner baulk ring (1), 1st synchronizer cone (2), and 1st outer baulk ring (3) to 1st main gear (4).

CAUTION:
Align the pawl (A) of the 1st synchronizer cone with the groove (B) of the 1st main gear.

4. Install spread spring to 1st-2nd synchronizer hub.

5. Install 1st-2nd synchronizer hub to mainshaft.

CAUTION:
Replace 1st-2nd synchronizer hub and 1st-2nd coupling sleeve as a set.

6. Heat the mainshaft bushing for 15 minutes at a temperature of 150°C, using a heat plate or an equivalent.

CAUTION:
• Never reuse mainshaft bushing.

• Never touch the mainshaft bushing with bare hands.

7. Remove the mainshaft bushing from the heat plate to install to the mainshaft, using pliers or an equivalent.

CAUTION:
Never touch the mainshaft bushing with bare hands.

8. Install mainshaft bushing (1) to mainshaft, using a drift (A) [Commercial service tool] and a press.

2 : 1st-2nd synchronizer hub

9. Install 1st-2nd coupling sleeve and spread spring to 1st-2nd synchronizer hub.

CAUTION:
Replace 1st-2nd synchronizer hub and 1st-2nd coupling sleeve as a set.

10. Apply gear oil to 2nd inner baulk ring, 2nd synchronizer cone, and 2nd outer baulk ring.

CAUTION:
Replace 2nd inner baulk ring, 2nd synchronizer cone, and 2nd outer baulk ring as a set.

11. Install 2nd inner baulk ring, 2nd synchronizer cone, and 2nd outer baulk ring to 1st-2nd synchronizer hub.

12. Install 2nd main gear and thrust washer to mainshaft.

CAUTION:
Align the pawl of the 2nd synchronizer cone with the groove of the 2nd main gear.

13. Heat the mainshaft bushing for 15 minutes at a temperature of 150°C, using a heat plate or an equivalent.

CAUTION:
• Never reuse mainshaft bushing.

• Never touch the mainshaft bushing with bare hands.

14. Remove the mainshaft bushing from the heat plate to install to the mainshaft, using pliers or an equivalent.

CAUTION:
Never touch the mainshaft bushing with bare hands.

15. Install mainshaft bushing (1) to mainshaft, using a drift (A) [Commercial service tool] and a press.

2 : Thrust washer
3 : 2nd main gear

16. Install 3rd main gear to mainshaft.

17. Apply gear oil to 3rd baulk ring.

18. Install 3rd baulk ring to 3rd main gear.

19. Install 3rd-4th synchronizer hub to mainshaft.

CAUTION:
Replace 3rd-4th synchronizer hub and 3rd-4th coupling sleeve as a set.

20. Heat the mainshaft bushing for 15 minutes at a temperature of 150°C, using a heat plate or an equivalent.

CAUTION:
• Never reuse mainshaft bushing.

• Never touch the mainshaft bushing with bare hands.

21. Remove the mainshaft bushing from the heat plate to install to the mainshaft, using pliers or an equivalent.

CAUTION:
Never touch the mainshaft bushing with bare hands.

22. Install mainshaft bushing (1) to mainshaft, using a drift (A) [Commercial service tool] and a press.

2 : 3rd-4th synchronizer hub

23. Install mainshaft front bearing inner race, using a drift [Commercial service tool].

CAUTION:
• Never reuse mainshaft front bearing inner race.

• Replace mainshaft front bearing inner race and mainshaft front bearing outer race as a set.

Inspection

INSPECTION AFTER DISASSEMBLY

Mainshaft and Gear
Check the following items and replace if necessary.

• Damage, peeling, bend, uneven wear, and distortion of shaft.

• Excessive wear, damage, and peeling of gear.

Synchronizer Hub and Coupling Sleeve Check the following items and replace if necessary.

• Breakage, damage, and unusual wear on contact surface of coupling sleeve, synchronizer hub, and insert key.

• Coupling sleeve and synchronizer hub move smoothly.

Baulk Ring
Check contact surface of baulk ring cam and insert key for excessive wear, uneven wear, bend, and damage. Replace if necessary.

Bearing
Check bearing for damage and unsmooth rotation. Replace if necessary.