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7D
TRANSFER 7D-1
The aluminum transfer case directly connected to the
back of the transmission contains the input gear,
countershaft & gear, output rear shaft, output low gear
and output front shaft (for front drive) connected by
way of the hyvo-chain.
The transfer has such a selective mechanism as to
enable the shift control lever to make selection of high
speed (direct connection with transmission output:
main shaft), low speed (speed reduction by input
gear, counter gear and output low gear) or neutral by
way of the reduction sleeve located between input
gear and output low gear, and selection of two-wheel-
drive (high speed only) or four-wheel-drive (high or
low speed) by way of the front drive clutch sleeve lo-cated at the center of the output rear shaft. Also, with
a synchronizer installed to the front drive clutch, it is
possible to change the drive mode between 2WD
(high speed only) and 4WD (high speed only) even
while running.
The front drive shift fork has an auxiliary spring to
make a smooth shift from 4H to 2H possible.
The case has an oil gutter and a plate at synchronizer
to provide proper lubrication even under the strict
conditions of use.
WARNING:
For towing the vehicle for the purpose of repair or
the like, follow the towing instructions in OWN-
ER'S MANUAL.
SECTION 7D
TRANSFER
CONTENTS
GENERAL DESCRIPTION7D-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS7D-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnosis Table7D-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE7D-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gear Oil7D-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Oil Seals7D-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Speedometer Driven Gear7D-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Rear Mounting7D-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Assembly7D-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dismounting7D-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Remounting7D-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR7D-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TIGHTENING TORQUE SPECIFICATIONS7D-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REQUIRED SERVICE MATERIALS7D-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOL7D-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION
Page 497 of 801
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7D-2 TRANSFER
DIAGNOSIS
DIAGNOSIS TABLE
Before attempting to repair the transfer or related components for any reason other than mechanical failure, the
condition and probable causes should be identified.
Transfer failures are revealed by shifting difficulties such as excessive shifting effort, gear clash, or gear grinding.
When any of these conditions occur, the following inspections should be made before disassembling the transfer.
1) Check transfer oil level for insufficient or incorrect oil. Refer to ªTransfer and Differential Oil Inspection and
Changeº in SECTION 0B ªMAINTENANCE AND LUBRICATIONº.
2) Check transfer mountings for wear or looseness.
3) Check gearshift control lever for distortion or excessive wear.
After performing the above inspections, refer to following diagnosis table.
Condition
Possible CauseCorrection
Gear slipping out of meshWorn shift fork shaft
Worn shift fork or synchronizer sleeve
Weak or damaged locating spring
Worn bearings on output rear shaft
Worn chamfered tooth on sleeve or gear
Missing or disengagement of circlip(s)Replace
Replace
Replace
Replace
Replace sleeve and gear
Install
Gears refusing to disengageWeakened or broken synchronizer spring
Distorted shift shaft or shift forkReplace
Replace
Hard shiftingWeakened front drive shift shaft spring
Distorted or mispositioned front drive shift
shaft circlip and washer
Inadequate or insufficient lubricant
Worn synchronizer ring
Worn chamfered tooth on sleeve or gear
Distorted shift shaftReplace
Replace
Replenish
Replace
Replace sleeve and gear
Replace
NoiseInadequate or insufficient lubricant
Damaged or worn bearing(s)
Damaged or worn gear(s)
Damaged or worn synchronizer ring
Damaged or worn chamfered tooth on
sleeve or gearReplenish
Replace
Replace
Replace
Replace
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7E-4 DIFFERENTIAL (FRONT)
Components and Functions
ComponentFunction
4WD switch
When the transfer shift lever is shifted to 4L or 4H position, this switch turns ON
and causes the 4WD control system to turn ON, unless it is shifted to N or 2H
within 1 second.
ECM or PCM
When the 4WD switch turns ON [unless it turns OFF within 1 second], this com-
ponent actuates the pump assembly. If the pressure in the air pump assembly
fails to increase higher than the set level even after the pump motor has run more
than 10 seconds, this component stops the motor to protect it.
Air pump assembly
Pump motor
Release valve
Pressure switchThe air pump assembly consists of a pump motor, release valve and a pressure
switch.
Pump motor:
Produces positive pressure which actuates the actuator.
Release valve:
Closes when transfer shift lever is shifted to 4H or 4L so that the positive pressure
is applied to the actuator, and opens when N or 2H to release the pressure to the
atmosphere.
Pressure switch:
Turns ON and OFF depending on the pressure level in the pump assembly
(whether higher or lower than the set pressure level). ECM or PCM detects the
pressure level through this switch.
Differential case assembly
Free axle hub
Axle lock clutch
ActuatorThe free axle hub, axle lock clutch and actuator are installed in the differential
left case. The positive pressure produced in the air pump assembly is applied
to the actuator which then pushes the axle lock clutch to be engaged with the free
axle hub. In this state, the drive force is transmitted to the front axle, resulting in
the 4WD mode.
When the actuator is free from the positive pressure [when it is under the atmo-
spheric pressure], the axle lock clutch is pushed back by the return spring force
and cannot be engaged with the free axle hub, resulting in the 2WD mode.
ª4WDº indicator lampIt lights up when 4WD control system is in the 4WD mode.