2-SPEED GCD

INSTALLATION MANUAL

DISASSEMBLY

THIS SEQUENCE APPLIES ONLY TO MANUAL/ MECHANICAL TYPE TRANSFER CASE.

NOTE: Transfer case does not need to be removed from the vehicle for GCD installation.

1. REMOVE REAR PROP- SHAFT. Discard shaft, a shorter shaft is supplied with GCD kit.

2. REMOVE REAR COMPANION FLANGE.

• (a) Using hammer and chisel release staked part of nut.
• (b) Using SST hold the companion flange whilst removing lock nut.
• (c) Remove the companion flange from shaft.

3. REMOVE 4WD INDICATOR LIGHT SWITCH.

4. REMOVE SPEEDO DRIVEN GEAR AND CABLE.

5. REMOVE REAR OUTPUT SHAFT REAR BEARING HOUSING Discard housing, a new one is supplied with GCD kit.

• (a) Remove the six bolts
• (b) Remove the speedometer drive gear and spacer. Discard spacer, a new one is supplied in kit.

6. REMOVE POWER TAKE-OFF COVER. This allows access to the transfer case bolts.

7. REMOVE IDLER GEAR SHAFT LOCK PLATE.

8. REMOVE TRANSFER REAR CASE.

• (a) Remove the bolts
• (b) Using a plastic hammer split and remove the transfer case half.

NOTE: Use extreme caution in splitting the case, keeping the split even so that the case does not jam. The separation is helped by tapping the idler shaft in.

9. REMOVE REAR OUTPUT SHAFT ASSEMBLY. Remove shift fork and shaft and slide out assembly. NOTE: Gear box must be in neutral.

10. REMOVE IDLER SHAFT O-RING.

11. REMOVE REAR OUTPUT SHAFT FRONT BEARING RETAINER.

12. INSTALL NEW BEARING CUP INTO RETAINER A new cup is supplied in GCD KIT

13. INSTALL NEW REAR OUTPUT SHAFT REAR BEARING CUP INTO GCD EXTENSION HOUSING. A new cup is supplied in GCD KIT

• (a) Install the ORIGINAL shim under the bearing cup.

to GCD 2 speed exploded drawing page ...

ASSEMBLY

PREPARE NEW REAR OUTPUT SHAFT ASSY

NOTE: High and low gears are re-assembled onto The new output shaft supplied in the kit.

1. REMOVE HIGH GEAR FROM TOYOTA OUTPUT SHAFT

• (a) Using snap ring pliers, remove snap ring.
• (b) Using a press and socket wrench, remove the following: Clutch Hub; Front bearing; High gear; Clutch sleeve.

2. REMOVE LOW GEAR FROM TOYOTA OUTPUT SHAFT

• (a) Using a press remove the following parts: Rear bearing; Low gear,

3. INSTALL HIGH GEAR TO NEW REAR OUTPUT SHAFT

NOTE: High gear is pressed onto end WITHOUT spline. Press on the following parts: High gear, Output shaft front bearing,

4. INSTALL LOW GEAR TO NEW REAR OUTPUT SHAFT

NOTE: Low gear is installed onto SPLINED end. Press on the following parts: Clutch sleeve, Low gear, Output shaft rear bearing.

5. INSTALL CLUTCH HUB ONTO GCD THRU-SHAFT

6. INSTALL SNAP RING ONTO THRU- SHAFT Select a snap ring that will allow minimal axial free play when Through Shaft is inserted into Rear Output Shaft

7. INSERT THRU-SHAFT INTO REAR OUTPUT SHAFT ASSEMBLY Insert Thru-shaft into High gear end of Output shaft.

SLEEVE TO FRONT OUTPUT SHAFT Install clutch sleeve with shift fork and shaft.

9. INSTALL REAR OUTPUT SHAFT FRONT BEARING RETAINER

10. INSTALL REAR O

ASSEMBLY INTO TRANSFER CASE

8. INSTALL CLUTCH

UTPUT SHAFT ASSEMBLY WITH SHIFT FORK AND SHAFT TO FRONT OUTPUT SHAFT

11. STICK THRUST WASHER TO TRANSFER REAR CASE

12. INSTALL TRANSFER REAR CASE

• (a) Place a new gasket on the front case.
• (b) Install the rear case.
• (c) Apply Loctite to the two bolts, and install and torque as shown.

Torque: 650 kg-cm (47 ft.lb,64 N-m)

• (d) Install and torque other bolts

Torque:

• 17mm 650 kg-cm (47ft-lb, 64 N-m)
• 14mm 400 kg-cm (29 ft-lb, 39 N-m)

13. INSTALL IDLER SHAFT O-RING AND LOCK PLATE

• (a) Align the shaft groove to the bolt hole.
• (b) Install O-ring on the shaft groove.
• (c) Using plastic hammer, drive in the shaft.
• (d) Install the lock plate and bolt. TORQUE THE BOLT: 130 kg-cm (9 ft-lb, 13Nm)

ADJUST REAR OUTPUT SHAFT PRELOAD

14. INSTALL GCD EXTENSION HOUSING WITH OUTPUT SHAFT REAR BEARING CUP

• (a) Place new gasket onto Extension Housing
• (b) Fit Extension Housing to Transfer rear case.
• (c) Torque the six new bolts supplied.
• (d) Shift the transfer lever to the "N" position.

15. INSTALL GCD REAR OUTPUT HEMI ASSEMBLY

• (a) Holding onto shaft, insert hemi assembly through Extension housing and slide onto splines of rear output shaft and thru-shaft.
• (b) Temporarily install rear companion flange nut.
• (c) Using a torque meter, measure the rear output preload. Preload: New Bearings 15 - 24.7 kg-cm (13 - 21.4 in-lb, 1.5 - 2.4 N-m) If the preload does not fall within the specifications, remove the Extension Housing and alter the shim under the bearing cup.
• (d) Remove the six Extension Housing bolts and re-install using Loctite and torque as follows Torque: 350 kg-cm (25 ft-lb, 34 N-m)

16. INSTALL SPEEDO DRIVE GEAR ONTO SHAFT

17. INSTALL NEW SPACER ONTO SHAFT Supplied in GCD kit.

18. INSTALL NEW SPEEDO DRIVE HOUSING Supplied in GCD kit.

• (a) Place new gasket onto housing
• (b) Apply Loctite to the six bolts. (Toyota originals)
• (c) Install and torque as follows Torque: 350 kg-cm (25 ft-lb, 34 N-m)

19. INSTALL REAR OUTPUT SHAFT ROLLER BEARING INTO SPEEDO DRIVE HOUSING Using suitable tool tap bearing onto shaft and seat into Housing.

NOTE: Install bearing with open side facing inwards.

20. INSTALL CIRCLIP INTO SPEEDO DRIVE HOUSING

21. INSTALL NEW DUST DEFLECTOR ONTO REAR COMPANION FLANGE (Supplied with GCD kit) New deflector is same as front to suit speedo housing.

22. INSTALL REAR COMPANION FLANGE

• (a) Install the companion flange.
• (b) Using SST to hold companion flange, install the companion flange lock nut. TORQUE: 1,300 kg-cm (94 ft-lb, 127Nm)
• (c) Stake companion flange lock nut.

23. INSTALL POWER-TAKE-OFF COVER.

• (a) Install the cover with gasket.
• (b) Apply liquid sealer to the two bolts and install and torque as follows: TORQUE: 170 kg-cm (12 ft-lb, 17Nm)
• (c) Install and torque the other bolts.

24. REPLACE SPEEDOMETER DRIVEN GEAR OIL SEAL. (Only if necessary)

25. INSTALL SPEEDOMETER DRIVEN GEAR AND CABLE. TORQUE: 130 kg-cm (9 ft-lb, 13Nm)

26. INSTALL NEW REAR PROP- SHAFT. Supplied with GCD kit

27. INSTALL PLUG SPRING AND LOCKING BALL

28. INSTALL 4WD INDICATOR LIGHT SWITCH

GCD OPERATIONAL TEST

The GCD is designed to un-lock and re-lock the common drive to front and rear axles when one axle attempts to overdrive the other axle during cornering.

NOTE: The above de-coupling action operates in both forward and reverse gears.

DE-COUPLE SIMULATION

1. With the vehicle chocked for safety at the REAR wheels raise the front axle wheels off the ground.

2. FIRST LIGHTLY rotate the PROP-SHAFT of the raised axle clockwise and anti-clockwise.

Observation: The transfer case common axle drive should appear to be solid and not capable of independent drive.

3. NOW FIRMLY rotate the driveshaft of the raised axle and the de-coupling can be felt as the prop-shaft breaks out and spins freely. Reverse the rotation of the raised axle prop-shaft and the re-coupling will occur.

4. Lower the raised axle and repeat the steps to check the REAR axle.

FOR OPTIMUM PERFORMANCE

NOTE:

1. It is very important that all 4 wheels are of matching diameter for optimum traction and performance.

2. During cornering, the GCD can be heard indexing as it un- locks and re-locks. This is quite normal.

return to Gearing Dynamics home page... ... to GCD 2 speed exploded drawing page