four wheel drive OPEL FRONTERA 1998 User Guide

ENGINE MECHANICAL 6A – 93
DISASSEMBLY
1. Cylinder Head Assembly
Refer to “Cylinder Head” in this manual.
2. Cylinder Head Gasket.
3. Flywheel
4. Cylinder Block Rear Plate (A/T), or Flywheel
housing (M/T).
5. Crankshaft Rear Oil Seal.
Install the special tool as shown in the illustration
and remove the oil seal.
Oil Seal Remover: 5-8840-2360-0
6. Retainer
7. Timing Gear Case Cover
8. Crankshaft Front Oil Seal
1) Use a plastic hammer and a screwdriver to tap
around the oil seal to free it from the gear case
cover.
9. Timing Gears
Refer to “Timing Gear” in this manual.
10. Timing gear case
11. Gasket
12. Balance shaft right
13. Crank case assembly
14. Piston cooling oil pipe
15. Piston assembly
16. Main bearing cap
17. Crankshaft assembly
18. Cylinder block side cover right and left
19. Cylinder block
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is
discovered during inspection.
1. Remove the cylinder head gasket and any other
material adhering to the upper surface of the
cylinder block.
Be very careful not to allow any material to
accidentally drop into the cylinder block.
Be very careful not to scratch the cylinder block.
2. Carefully remove liquid gasket, which was used
when assembled, from gear case, rear oil seal
retainer and crank case.
3. Wipe the cylinder block clean and visually check it.
4. Use a straight edge and a feeler gauge to measure
the four sides and the two diagonals of the cylinder
block upper face.
If the measured values exceed the limit, the cylinder
block must be replaced.
Limit: 0.20 mm (0.0079 in)
015RV002
012RW122

7A–3 AUTOMATIC TRANSMISSION (4L30–E)
Service Precaution
WARNING: IF SO EQUIPPED WITH A
SUPPLEMENTAL RESTRAINT SYSTEM (SRS),
REFER TO THE SRS COMPONENT AND WIRING
LOCATION VIEW IN ORDER TO DETERMINE
WHETHER YOU ARE PERFORMING SERVICE ON OR
NEAR THE SRS COMPONENTS OR THE SRS
WIRING. WHEN YOU ARE PERFORMING SERVICE
ON OR NEAR THE SRS COMPONENTS OR THE SRS
WIRING, REFER TO THE SRS SERVICE
INFORMATION. FAILURE TO FOLLOW WARNINGS
COULD RESULT IN POSSIBLE AIR BAG
DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.
Construction
A07RS001
Legend
(1) Torque Converter Clutch (TCC)
(2) Fourth Clutch (C4)
(3) Overrun Clutch (OC)
(4) Overdrive Unit
(5) Reverse Clutch (RC)
(6) Second Clutch (C2)(7) Third Clutch (C3)
(8) Ravigneaux Planetary Gear Set
(9) Brake Band (B)
(10) Overdrive Free Wheel (One Way Clutch)
(OFW)
(11) Sprag Free Wheel (One Way Clutch) (PFW)

CLUTCH7C–11
1. Use a straight edge and a feeler gauge to measure
the pressure plate friction surface flatness in four
directions.
2. If any of the measured values exceeds the specified
limit, the pressure plate must be replaced.
Pressure Plate Warpage
Limit: 0.3 mm (0.012 in)
Clutch Cover
201RS004
1. Visually check the entire clutch cover for excessive
wear, cracking, and other damage.
2. The clutch cover must be replaced if any of these
conditions are present.
Clutch Set Force
201RS005
1. Invert the pressure plate assembly.2. Place a new driven plate over the pressure plate. A
metal sheet with “A” thickness of 8.3 mm (0.327 in)
may be used in place of the driven plate.
3. Compress the pressure plate assembly until the
distance “B” becomes 12 mm (0.472 in).
4. Note the pressure gauge reading.
5. If the measured value is less than the specified limit,
the pressure plate assembly must be replaced.
Clutch Set Force
Standard: 7208 N ( 1621 lb)
Limit: 6468 N (1454 lb)
Diaphragm Spring Finger Height
201RW009
Legend
(1) Release Side
1. Place a new driven plate or a 8.3 mm (0.327 in)
spacer beneath the pressure plate.
2. Fully compress the pressure plate and diaphragm
spring.
3. There are two ways to do this.
4. Use a bench press to press down on the assembly
from the top.
5. Tighten the fixing bolts.
NOTE: Preload on diaphragm spring finger must be 49 –
98 N (11 – 22 lb) in direction of release, when clutch cover
assembly is bolted to the flywheel.
6. Measure the spring height from base to spring tip “A”.
If the measured value exceeds the specified limit, the
pressure plate assembly must be replaced.
Diaphragm Spring Finger Height
Standard: 49.9 mm – 51.9 mm (1.965 in –
2.043 in)

8A–18LIGHTING SYSTEM
Lighting Switch (Combination Switch)
Removal
1. Disconnect the battery ground cable.
2. Remove the instrument panel driver lower cover(5).
Refer to the Instrument Panel Assembly in Body
Structure section.
3. Remove seven screws to remove the steering
cowl(4).
4. Disconnect the SDM (air bag controller) connector
located at lower of the instrument panel driver lower
cover.
5. Remove four fixing screws and disconnect the driver
inflator module connector to remove the driver inflator
module(3).
CAUTION: When carrying a live inflator module,
make sure the bag opening is pointed away from
y o u . I n c a s e o f a n a c c i d e n t a l d e p l o y m e n t , t h e b a g w i l l
then deploy with minimal chance of injury. Never
carry the inflator module by the wires or connector
on the underside of the module.
When placing a live inflator module on a bench or
other surface, always face the bag and trim cover up,
away from the surface. This is necessary so that a
free space is provided to allow the air bag to expand
in the unlikely event of accidental deployment.
6. Remove the steering wheel(2).
Refer to the Steering Wheel in Steering section.
7. Disconnect the SRS coil assembly connector,
remove four fixing screws to remove the SRS coil
assembly(1).
8. Disconnect the lighting switch connector, remove four
fixing screws to remove the lighting switch(6).
825RS039
Installation
To install, follow the removal steps in the reverse order,
noting the following points.1. Check to see if the vehicle is in the straight driving
condition and turn the rotary section of the SRS coil
assembly provided to the upper surface of the lighting
switch (combination switch) counterclockwise fully
until it stops.
Then from where it stops, turn it back about 3
rotations to set the alignment marks(7) together
before installing the steering wheel.
825RW099
2. Tighten the steering shaft nut to the specified torque.
Torque: 34 Nꞏm (3.5 kgꞏm/25 lb ft)
3. When connect the double lock type of inflator module
connector, insert the connector completely and lock
at outside.
Imperfect locking may cause malfunction of SRS
system circuit.
4. When installing the steering cowl(11), be sure to pass
the harnesses through the route as shown in the
figure so that the starter switch harness(8), the
combination switch harness(9) and inflator module
harness(10) will not get caught.
431RW014

SUPPLEMENTAL RESTRAINT SYSTEM 9J–18
6. Prepare four 15 inch or larger tires without wheel and
two same size tires with wheels.
827RW056
7. How to fix Driver air bag.
1. Fix the air bag with its trim cover up on a tire with a
wheel using an automobile use wire harness,
(core size: 0.05 inch) or a wire trebly at two or
more points.
2. Connect SRS air bag assembly to the double pole
extension cord of the air bag deployment
harness.
Do not connect the deployment harness to a pow-
er source until air bag deployment.
(If connected the SRS air bag assembly deploys
immediately)
NOTE: Ensure that the pigtail adapter is firmly seated into
the air bag assembly connector. Failure to fully seat the
connectors may leave the shorting bar located in the air
bag assembly connector functioning (shorting the
deployment circuit) and may result in non deployment of
the air bag assembly.
827RW054
3. Place three tires without wheel on the tire on
which air bag is fixed and a tire with a wheel on
top.
Bind the five tires with a rope so that the tires may
not collapse.
827RW053
Legend
(A) 10 m (33 feet) or more
8. How to fix Passenger air bag.
1. Fix the air bag with its trim cover side fixing the
center of a tire without a wheel using an
automobile use wire harness, (core size: 0.05
inch) or a wire trebly at two or more points.
901RX045
2. Connect Supplemental Restraint System (SRS)
air bag assembly to the deployment harness
double pole extension cord end. Be sure not to
connect the deployment harness to a power
source. (If connected the SRS air bag assembly
deploys immediately).

DIFFERENTIAL (REAR 220mm)
4A2A–3
Diagnosis
Many noises that seem to come from the rear axle
actually originate from other sources such as tires, road
surface, wheel bearings, engine, transmission, muffler, or
body drumming. Investigate to find the source of the
noise before disassembling the rear axle. Rear axles, like
any other mechanical device, are not absolutely quiet but
should be considered quiet unless some abnormal noise
is present.
To make a systematic check for axle noise, observe the
following:
1. Select a level asphalt road to reduce tire noise and
body drumming.
2. Check rear axle lubricant level to assure correct level,
and then drive the vehicle far enough to thoroughly
warm up the rear axle lubricant.
3. Note the speed at which noise occurs. Stop the
vehicle and put the transmission in neutral. Run the
engine speed slowly up and down to determine if the
noise is caused by exhaust, muffler noise, or other
engine conditions.
4. Tire noise changes with different road surfaces; axle
noises do not. Temporarily inflate all tires to 344 kPa
(3.5kg/cm
2, 50 psi) (for test purposes only). This will
change noise caused by tires but will not affect noise
caused by the rear axle.
Rear axle noise usually stops when coasting at
speeds under 48 km/h (30 mph); however, tire noise
continues with a lower tone. Rear axle noise usually
changes when comparing pull and coast, but tire
noise stays about the same.
Distinguish between tire noise and rear axle noise by
noting if the noise changes with various speeds or
sudden acceleration and deceleration. Exhaust and
axle noise vary under these conditions, while tire
noise remains constant and is more pronounced at
speeds of 32 to 48 km/h (20 to 30 mph). Further check
for tire noise by driving the vehicle over smooth
pavements or dirt roads (not gravel) with the tires at
normal pressure. If the noise is caused by tires, it will
change noticeably with changes in road surface.
5. Loose or rough front wheel bearings will cause noise
which may be confused with rear axle noise; however,
front wheel bearing noise does not change when
comparing drive and coast. Light application of the
brake while holding vehicle speed steady will often
cause wheel bearing noise to diminish. Front wheel
bearings may be checked for noise by jacking up the
wheels and spinning them or by shaking the wheels to
determine if bearings are loose.
6. Rear suspension rubber bushings and spring
insulators dampen out rear axle noise when correctly
installed. Check to see that there is no link or rod
loosened or metal–to–metal contact.
7. Make sure that there is no metal–to–metal contact
between the floor and the frame.
After the noise has been determined to be in the axle, the
type of axle noise should be determined, in order to make
any necessary repairs.
Gear Noise
Gear noise (whine) is audible from 32 to 89 km/h (20 to 55
mph) under four driving conditions.
1. Driving under acceleration or heavy pull.
2. Driving under load or under constant speed.
3. When using enough throttle to keep the vehicle from
driving the engine while the vehicle slows down
gradually (engine still pulls slightly).
4. When coasting with the vehicle in gear and the throttle
closed. The gear noise is usually more noticeable
between 48 and 64 km/h (30 and 40 mph) and 80 and
89 km/h (50 and 55 mph).
Bearing Noise
Bad bearings generally produce a rough growl or grating
sound, rather than the whine typical of gear noise.
Bearing noise frequently “wow–wows” at bearing rpm,
indicating a bad pinion or rear axle side bearing. This
noise can be confused with rear wheel bearing noise.
Rear Wheel Bearing Noise
Rear wheel bearing noise continues to be heard while
coasting at low speed with transmission in neutral. Noise
may diminish by gentle braking. Jack up the rear wheels,
spin them by hand and listen for noise at the hubs.
Replace any faulty wheel bearings.
Knock At Low Speeds
Low speed knock can be caused by worn universal joints
or a side gear hub counter bore in the cage that is worn
oversize. Inspect and replace universal joints or cage and
side gears as required.
Backlash Clunk
Excessive clunk on acceleration and deceleration can be
caused by a worn rear axle pinion shaft, a worn cage,
excessive clearance between the axle and the side gear
splines, excessive clearance between the side gear hub
and the counterbore in the cage, worn pinion and side
gear teeth, worn thrust washers, or excessive drive pinion
and ring gear backlash. Remove worn parts and replace
as required. Select close–fitting parts when possible.
Adjust pinion and ring gear backlash.

4A2B–4DIFFERENTIAL (REAR 244mm)
Diagnosis
Many noises that seem to come from the rear axle
actually originate from other sources such as tires, road
surface, wheel bearings, engine, transmission, muffler, or
body drumming. Investigate to find the source of the
noise before disassembling the rear axle. Rear axles, like
any other mechanical device, are not absolutely quiet but
should be considered quiet unless some abnormal noise
is present.
To make a systematic check for axle noise, observe the
following:
1. Select a level asphalt road to reduce tire noise and
body drumming.
2. Check rear axle lubricant level to assure correct level,
and then drive the vehicle far enough to thoroughly
warm up the rear axle lubricant.
3. Note the speed at which noise occurs. Stop the
vehicle and put the transmission in neutral. Run the
engine speed slowly up and down to determine if the
noise is caused by exhaust, muffler noise, or other
engine conditions.
4. Tire noise changes with different road surfaces; axle
noises do not. Temporarily inflate all tires to 344 kPa
(3.5kg/cm
2, 50 psi) (for test purposes only). This will
change noise caused by tires but will not affect noise
caused by the rear axle.
Rear axle noise usually stops when coasting at
speeds under 48 km/h (30 mph); however, tire noise
continues with a lower tone. Rear axle noise usually
changes when comparing pull and coast, but tire
noise stays about the same.
Distinguish between tire noise and rear axle noise by
noting if the noise changes with various speeds or
sudden acceleration and deceleration. Exhaust and
axle noise vary under these conditions, while tire
noise remains constant and is more pronounced at
speeds of 32 to 48 km/h (20 to 30 mph). Further check
for tire noise by driving the vehicle over smooth
pavements or dirt roads (not gravel) with the tires at
normal pressure. If the noise is caused by tires, it will
change noticeably with changes in road surface.
5. Loose or rough front wheel bearings will cause noise
which may be confused with rear axle noise; however,
front wheel bearing noise does not change when
comparing drive and coast. Light application of the
brake while holding vehicle speed steady will often
cause wheel bearing noise to diminish. Front wheel
bearings may be checked for noise by jacking up the
wheels and spinning them or by shaking the wheels to
determine if bearings are loose.
6. Rear suspension rubber bushings and spring
insulators dampen out rear axle noise when correctly
installed. Check to see that there is no link or rod
loosened or metal–to–metal contact.
7. Make sure that there is no metal–to–metal contact
between the floor and the frame.
After the noise has been determined to be in the axle, the
type of axle noise should be determined, in order to make
any necessary repairs.
Gear Noise
Gear noise (whine) is audible from 32 to 89 km/h (20 to 55
mph) under four driving conditions.
1. Driving under acceleration or heavy pull.
2. Driving under load or under constant speed.
3. When using enough throttle to keep the vehicle from
driving the engine while the vehicle slows down
gradually (engine still pulls slightly).
4. When coasting with the vehicle in gear and the throttle
closed. The gear noise is usually more noticeable
between 48 and 64 km/h (30 and 40 mph) and 80 and
89 km/h (50 and 55 mph).
Bearing Noise
Bad bearings generally produce a rough growl or grating
sound, rather than the whine typical of gear noise.
Bearing noise frequently “wow–wows” at bearing rpm,
indicating a bad pinion or rear axle side bearing. This
noise can be confused with rear wheel bearing noise.
Rear Wheel Bearing Noise
Rear wheel bearing noise continues to be heard while
coasting at low speed with transmission in neutral. Noise
may diminish by gentle braking. Jack up the rear wheels,
spin them by hand and listen for noise at the hubs.
Replace any faulty wheel bearings.
Knock At Low Speeds
Low speed knock can be caused by worn universal joints
or a side gear hub counter bore in the cage that is worn
oversize. Inspect and replace universal joints or cage and
side gears as required.
Backlash Clunk
Excessive clunk on acceleration and deceleration can be
caused by a worn rear axle pinion shaft, a worn cage,
excessive clearance between the axle and the side gear
splines, excessive clearance between the side gear hub
and the counterbore in the cage, worn pinion and side
gear teeth, worn thrust washers, or excessive drive pinion
and ring gear backlash. Remove worn parts and replace
as required. Select close–fitting parts when possible.
Adjust pinion and ring gear backlash.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2–2
General Description
C07RW014–1
TOD (Torque on Demand) system is traction state control
system to vehicle.
Transfer Position and Drive Mode
Three drive modes can be selected through operation of
4WD AUTO switch and transfer lever.
Transfer Position
4WD AUTO SWModeDrive mode
HIGHON (NORMAL)2HRear wheel drive
OFF (PUSHED)TODElectronically controlled torque split
four wheel drive
4LON/OFF4LLow-speed mechanical lock-up four
wheel drive
The electronic control unit (ECU) judges the signals from
the transfer lever and 4WD AUTO switch, and controls
the transfer drive mode and shift-on-the-fly system
status.
TOD Control
The TOD position usually drives the rear wheels, and
transmits the torque to the front wheels with the help of
electronically controlled torque split mechanism
according to running conditions encountered. The driving
force is directly transmitted to the rear wheels. This force
is split by the transfer and delivered to the front wheels.
The magnitude of the torque transmitted to the front
wheels is controlled by changing the pressing force of the
multi plate disk clutch built in the transfer unit. Thepressing force of the clutch is controlled by changing the
duty cycle to the electromagnetic coil mounted to the rear
of the clutch. When the clutch is completely disengaged,
the rear wheels are driven. When the clutch is completely
engaged, a rigid four wheel drive mode is obtained. The
torque split status is controlled continuously between the
rear wheel and four wheel drive modes. This system
includes front and rear speed sensors, and receives
throttle position sensor information from ECM.
The control unit receives signals sent from these sensors
and changes the pressing force of the multi plate disk
clutch to determine the torque distribution on the front and
rear wheels. Therefore, when the slip of the rear wheels is
increased against the current torque level in the normal
rear wheel drive mode, the control unit detects the slip

TRANSFER CASE (STANDARD TYPE)
4D1–7
A/T, WO/Shift On The Fly, WO/4WD Switch, model
A07RW055
The transfer case is used to provide a means of providing
power flow to the front axle. The transfer case also
provides a means of disconnecting the front axle,
providing better fuel economy and quieter operation when
the vehicle is driven on improved roads where four wheel
drive is not required. In addition, the transfer case
provides an additional gear reduction when placed in low
range, which is useful when difficult off–road conditions
are encountered.
A floor mounted shift lever is used to select the high–low
range. When four wheel drive switch has been turned on,
the four wheel drive indicator light is designed to come on
when the front axle has been engaged.

4D2–41 TRANSFER CASE (TOD)
Main Data and Specifications
Leading Particulars
Ty p eTransfer case with low range reduction mechanism
2H Rear wheel drive
TOD Electronically controlled torque split four wheel drive
4L Low-speed mechanical lock-up four wheel drive
Control systemFloor direct control
Gear ratioH1.000
L2.480
Oil quantity, Lit1.9
OilAT F D E X R O N-IIE or ATF DEXRON-III
Torque Specifications
E04RW012