1999 SUZUKI GRAND VITARA hub

YH4
GRAND
VITARA
7A1
MANUAL TRANSMISSION (TYPE 2) 7A1-1
TYPE 2
GENERAL DESCRIPTION7A1-1 . . . . . . . . . . . . . .
DIAGNOSIS7A1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE7A1-3 . . . . . . . . . . . . . . . .
Gear Oil 7A1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shift Control Levers 7A1-4. . . . . . . . . . . . . . . . . . .
Switches 7A1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Rear Mounting 7A1-4. . . . . . . . . . . . . . . . Dismounting / Remounting of
Trans. Unit 7A1-4. . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR7A1-4 . . . . . . . . . . . . . . . . . . . . . . . . .
TIGHTENING TORQUE
SPECIFICATIONS7A1-5 . . . . . . . . . . . . . . . . . . . .
REQUIRED SERVICE MATERIALS7A1-5 . . . . . .
The manual transmission consists of the input shaft,
main shaft, counter shaft and reverse gear which are
installed in the aluminum and castings cases. Its
gears are of forward five speeds in synchro mesh and
reverse one speed in sliding idler gear arrangement
system.
The main shaft gears are held by the needle bear-
ings and on them the synchronizer rings and syn-
chronizer sleeve & hubs are assembled.
The gear shift lever case is located at the upper be-
hind the transmission case and has a cam which pre-
vents direct gear shift from the 5th speed gear to the
reverse gear.As the aluminum and castings cases are sealed with
liquid type gasket, it is necessary to use genuine seal-
ant or its equivalent on its mating surfaces when reas-
sembling them. Also, the case fastening bolts must be
tightened to specified torque by means of the torque
wrench and tightening over or below the specified
torque should be avoided.
The description under ON-VEHICLE SERVICE in this
section covers the transfer partially which is next to
the transmission as well, but their gear boxes are in-
dependent and each of them has its own drain and
level / filler plugs for the oil change or the level check.
For the repair procedure of the transfer unit, refer to
Section 7D.
SECTION 7A1
MANUAL TRANSMISSION
(TYPE 2)
CONTENTS
GENERAL DESCRIPTION

YH4
GRAND
VITARA
CLUTCH 7C1-3
DIAGNOSIS
ConditionPossible CauseCorrection
Slipping
Improper clutch pedal free travel.

Worn or oily clutch disc facing.

Warped disc, pressure plate or flywheel
surface.

Weakened diaphragm spring.

Master cylinder piston or seal cup not returning.Bleed air or replace master
cylinder.
Replace disc.
Replace disc, clutch cover or
flywheel.
Replace clutch cover.
Repair master cylinder.
Dragging clutch
Improper clutch pedal free travel.

Weakened diaphragm spring, or worn spring tip.

Rusted input shaft splines.

Damaged or worn splines of transmission
input shaft.

Excessively wobbly clutch disc.

Clutch facings broken or dirty with oil.

Fluid leakage.Bleed air or replace master
cylinder.
Replace clutch cover.
Lubricate.
Replace input shaft.
Replace disc.
Replace disc.
Repair or replace.
Clutch vibration
Glazed (glass-like) clutch facings.

Clutch facings dirty with oil.

Release bearing slides unsmoothly on input
shaft bearing retainer.

Wobbly clutch disc, or poor facing contact.

Weakened torsion springs in clutch disc.

Clutch disc rivets loose.

Distorted pressure plate or flywheel surface.

Weakened or loosened engine mounting
bolt or nut.Repair or replace disc.
Replace disc.
Lubricate or replace input
shaft bearing retainer.
Replace disc.
Replace disc.
Replace disc.
Replace clutch cover or flywheel.
Retighten or replace mounting.
Noisy clutch
Worn or broken release bearing.

Input shaft front bearing worn down.

Excessive rattle of clutch disc hub.

Cracked clutch disc.

Pressure plate and diaphragm spring rattling.Replace release bearing.
Replace input shaft bearing.
Replace disc.
Replace disc.
Replace clutch cover.
Grabbing clutch
Clutch disc facings soaked with oil.

Clutch disc facings excessively worn.

Rivet heads showing out of facing.

Weakened torsion springs.Replace disc.
Replace disc.
Replace disc.
Replace disc.

YH4
GRAND
VITARA
1. 4WD switch
2. Transfer
3. Blank
4. Blank
5. ECM or PCM
6. Glove box7. Air pump assembly
8. Actuator
9. Axle lock clutch
10. Free axle hub
11. 4WD indicator lamp
7E-2 DIFFERENTIAL (FRONT)
4WD CONTROL SYSTEM
When the 4WD switch is turned ON by shifting the transfer shift lever, ECM (PCM) (G16 and J20 engine models)
or 4WD controller (H25 engine model) actuates (energizes) the air pump assembly. Then positive pressure is sent
from the air pump assembly to the actuator installed to the differential case and causes the axle lock clutch and
the free axle hub in the differential case to be engaged, resulting in the 4WD mode. Only when running in the 4WD
mode, front axles are joined to differential case, and they become free when 2WD mode is used (or when transfer
shift lever is shifted to N position), thereby reducing the power loss.

YH4
GRAND
VITARA
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.