1998 OPEL FRONTERA oil level

6. Remove any excess oil resulting from installing the
new seal parts from the shaft and inside the
compressor neck.
7. Install the clutch plate and hub assembly as
described previously.8. Reinstall compressor belt and tighten bracket.
9. Evacuate and charge the refrigerant system.
COMPRESSOR PRESSURE RELIEF VALVE
Removal
1. Recover the refrigerant using Refrigerant Recovery
System.
2. Remove old pressure relief valve.
Installation
1. Clean valve seat area on rear head.2. Lubricate O-ring of new pressure relief valve and
O-ring assembly with new 525 viscosity refrigerant
oil. Install new valve and torque in place, 9.0 Nꞏm
(6.1 ft lbs)
3. Evacuate and recharge the system.
4. Leak test system.
COMPRESSOR OIL
Compressor Oil Check
The oil used to lubricate the compressor is circulating
with the refrigerant.
Whenever replacing any component of the system or a
large amount of gas leakage occurs, add oil to maintain
the original amount of oil.
Checking and Adjusting Oil Quantity for
Used Compressor
1. Perform oil return operation. Refer to Oil Return
Operation in this section.
2. Discharge and recover refrigerant and remove the
compressor.
3. Drain the compressor oil and measure the extracted
oil with a measuring cylinder.
4. If the amount of oil drained is much less than 90 cc
(3.0 fl. oz.), some refrigerant may have leaked out.
Conduct a leak tests on the connections of each
system, and if necessary, repair or replace faulty
parts.
5. Check the compressor oil contamination. (Refer to
Contamination of Compressor Oil in this section.)
6. Adjust the oil level following the next procedure
below.7. Install the compressor, then evacuate, charge and
perform the oil return operation.
8. Check system operation.
When it is impossible to preform oil return
operation, the compressor oil should be checked in
the following order:
1. Discharge and recover refrigerant and remove the
compressor.
2. Drain the compressor oil and measure the extracted
oil with a measuring cylinder.
3. Check the oil for contamination.
4. If more than 90 cc (3.0 fl. oz.) of oil is extracted from
the compressor, supply the same amount of oil to
the compressor to be installed. If the amount of oil
extracted is less than 90 cc (3.0 fl. oz.), recheck the
compressor oil in the following order:
5. Supply 90 cc (3.0 fl. oz.) of oil to the compressor
and install it onto the vehicle.
6. Evacuate and recharge with the proper amount of
refrigerant.
7. Perform the oil return operation.
8. Remove the compressor and recheck the amount of
oil.
9. Adjust the compressor oil, if necessary.
Checking and Adjusting for Compressor
Replacement
The oil is not charged in compressor (service parts). So
it is necessary to charge the proper amount of oil to the
new compressor. (Oil Capacity)
Capacity total in system 150 cc (5.0 fl.oz)
Compressor (Service 150 cc (5.0 fl.oz)
parts) charging amount
(Collected Amount) (Charging Amount)
more than 90 cc same as collected
(3.0 fl.oz) amount
less than 90 cc (3.0 fl.oz) 90 cc (3.0 fl.oz)
(Collected Amount) (Charging Amount)
more than 90 cc same as collected
(3.0 fl.oz) amount
less than 90 cc (3.0 fl.oz) 90 cc (3.0 fl.oz)

1. Perform oil return operation.
2. Discharge and recover the refrigerant and remove
the compressor.
3. Drain the compressor oil and measure the extracted
oil.
4. Check the compressor oil for contamination.
5. Adjust the oil level as required.
6. Evacuate, charge and perform the oil return
operation.
7. Check the system operation.
Contamination of Compressor Oil
Unlike engine oil, no cleaning agent is added to the
compressor oil. Even if the compressor runs for a long
period of time (approximately one season), the oil never
becomes contaminated as long as there is nothing
wrong with the compressor or its method of use.
Inspect the extracted oil for any of the following
conditions:
The capacity of the oil has increased.
The oil has changed to red.
Foreign substances, metal powder, etc., are present
in the oil.
If any of these conditions exists, the compressor
oil is contaminated. Whenever contaminated
compressor oil is discovered, the receiver/drier
must be replaced.
Oil Return Operation
There is close affinity between the oil and the
refrigerant. During normal operation, part of the oil
recirculates with the refrigerant in the system. When
checking the amount of oil in the system, or replacing
any component of the system, the compressor must be
run in advance for oil return operation. The procedure
is as follows:
1. Open all the doors and the engine hood.
2. Start the engine and air conditioning switch to "ON"
and set the fan control knob at its highest position.
3. Run the compressor for more than 20 minutes
between 800 and 1,000 rpm in order to operate the
system.
4. Stop the engine.
Replacement of Component Parts
When replacing the system component parts, supply
the following amount of oil to the component parts to be
installed.
Compressor Leak Testing (External and
Internal)
Bench-Check Procedure
1. Install test plate J-39893 on rear head of compressor.
2. Using Refrigerant Recovery System, attach center
hose of manifold gage set on charging station to a
refrigerant drum standing in an upright drum.
3. Connect charging station high and low pressure
lines to corresponding fittings on test plate J-39893.
Suction port (low-side) of compressor has large
internal opening. Discharge port (high-side) has
smaller internal opening into compressor and
deeper recess.
4. Open low pressure control, high pressure control
and refrigerant control on charging station to allow
refrigerant vapor to flow into compressor.
5. Using a leak detector, check for leaks at pressure
relief valve, rear head switch location, compressor
front and rear head seals, center cylinder seal,
through bolt head gaskets and compressor shaft
seal. After checking, shut off low pressure control
and high-pressure control on charging station.
6. If an external leak is present, perform the necessary
corrective measures and recheck for leaks to make
certain the leak has been connected.
7. Recover the refrigerant.
8. Disconnect both hoses from the test plate J-39893.
9. Add 90 ml (3 oz.) new PAG lubricant to the
compressor assembly. Rotate the complete
compressor assembly (not the crankshaft or drive
plate hub) slowly several turns to distribute oil to all
cylinder and piston areas.
10. Install a M9
1.25 threaded nut on the compressor
crankshaft if the drive plate and clutch assembly are
not installed.
11. Using a box-end wrench or socket and handle,
rotate the compressor crankshaft or clutch drive
plate on the crankshaft several turns to insure
piston assembly to cylinder wall lubrication.
12. Using Refrigerant Recovery System, connect the
charging station high-pressure line to the test plate
J-39893 high-side connector.
13. Using Refrigerant Recovery System, connect the
charging station low-pressure line to the low
pressure port of the test plate J-39893. Oil will drain
out of the compressor suction port if the compressor
is positioned with the suction port downward. (Component parts to be (Amount of Oil)
installed)
Evaporator 50 cc (1.7 fl. oz.)
Condenser 30 cc (1.0 fl. oz.)
Receiver/dryer 30 cc (1.0 fl. oz.)
Refrigerant line (one 10 cc (0.3 fl. oz.)
piece)
(Amount of oil drained (Charging amount of oil
from used compressor) to new compressor)
more than 90 cc same as drained amount
(3.0 fl.oz)
less than 90 cc (3.0 fl.oz) 90 cc (3.0 fl.oz)

DIFFERENTIAL (FRONT) 4A1–2
Front Drive Axle
Diagnosis
ConditionPossible causeCorrection
Oil Leak At Front AxleWorn or defective oil seal.Replace the oil seal.
Front axle housing cracked.Repair or replace.
Oil Leak At Pinion ShaftToo much gear oil.Correct the oil level.
Oil seal worn or defective.Replace the oil seal.
Pinion flange loose or damaged.Tighten or replace.
Noises In Front Axle Drive Shaft
JointBroken or worn drive shaft joints and
bellows (BJ and DOJ).Replace the drive shaft joints and
bellows.
“Clank” When Accelerating From
“Coast”Loose drive shaft joint to output shaft
bolts.Tighten.
Damaged inner drive shaft joint.Replace.
Shudder or Vibration During
Acceleration
Excessive drive shaft joint angle.Repair.
AccelerationWorn or damaged drive shaft joints.Replace.
Sticking spider assembly (inner drive
shaft joint).Lubricate or replace.
Sticking joint assembly (outer drive
shaft joint).Lubricate or replace.
Vibration At Highway SpeedsOut of balance or out of round tires.Balance or replace.
Front end out of alignment.Align.
Noises in Front AxleInsufficient gear oil.Replenish the gear oil.
Wrong or poor grade gear oil.Replace the gear oil.
Drive pinion to ring gear backlash
incorrect.Adjust the backlash.
Worn or chipped ring gear, pinion
gear or side gear.Replace the ring gear, pinion gear or
side gear.
Pinion shaft bearing worn.Replace the pinion shaft bearing.
Wheel bearing worn.Replace the wheel bearing.
Differential bearing loose or worn.Tighten or replace.
Wanders and PullsWheel bearing preload too tight.Adjust the wheel bearing preload.
Incorrect front alignment.Adjust the front alignment.
Steering linkage loose or worn.Tighten or replace.
Steering gear out of adjustment.Adjust or replace the steering gear.
Tire worn or improperly inflated.Adjust the inflation or replace.
Front or rear suspension parts loose
or broken.Tighten or replace.
Front Wheel ShimmyWheel bearing worn or improperly
adjusted.Adjust or replace.
Incorrect front alignment.Adjust the front alignment.
Worn ball joint or bush.Replace the ball joint or bush.
Steering linkage loose or worn.Tighten or replace.
Steering gear out of adjustment.Tighten or replace.
Tire worn or improperly inflated.Replace or adjust the inflation.
Shock absorber worn.Replace the shock absorber.

DIFFERENTIAL (REAR 220mm)
4A2A–27
Pressure ring
425RS057
Legend
(3) Sliding surface with the friction disc. When
nicks or scratches are found, polish with an oil
stone and repair on a level block using a
compound.
(4) Sliding spherical surface with the pinion gear.
(5) Sliding surface with the side gear.
(6) V–shaped groove of the pressure ring and V
–shaped section of the pinion shaft.
(7) Fitting section with the case.
(8) Face contacting the inner surface of the
differential case. Repair burrs and nicks using
an oil stone.
Thrust washer
425RS058
Legend
(9) Sliding surface with the side gear or case.
(10) Peripheral groove of the side gear.
Repair light nicks and burrs using an oil stone.
Case
425RS059
Legend
(11) Contact surface with the spring disc.
(12) Inner groove of the differential cage B.
Repair light nicks and burrs using an oil stone.
425RS060

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 switch and transfer lever.
Transfer Position
TOD 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 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
electromagnetic multi plate disk clutch built in the transfer
unit. The pressing force of the clutch is controlled bychanging the voltage 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 throttle position sensor that monitors the
engine output.
The control unit receives signals sent from these sensors
and changes the pressing force of the electromagnetic
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

4C–3 DRIVE SHAFT SYSTEM
Diagnosis
ConditionPossible causeCorrection
Oil Leak At Front AxleWorn or defective oil seal.Replace the oil seal.
Front axle housing cracked.Repair or replace.
Oil Leak At Pinion ShaftToo much gear oil.Correct the oil level.
Oil seal worn or defective.Replace the oil seal.
Pinion flange loose or damaged.Tighten or replace.
Noises In Front Axle Drive Shaft
JointBroken or worn drive shaft joints and
bellows (BJ and DOJ).Replace the drive shaft joints and
bellows.
“Clank” When Accelerating From
“Coast”Loose drive shaft joint to output shaft
bolts.Tighten.
Damaged inner drive shaft joint.Replace.
Shudder or Vibration During
Acceleration
Excessive drive shaft joint angle.Repair.
AccelerationWorn or damaged drive shaft joints.Replace.
Sticking spider assembly (inner drive
shaft joint).Lubricate or replace.
Sticking joint assembly (outer drive
shaft joint).Lubricate or replace.
Vibration At Highway SpeedsOut of balance or out of round tires.Balance or replace.
Front end out of alignment.Align.
Noises in Front AxleInsufficient gear oil.Replenish the gear oil.
Wrong or poor grade gear oil.Replace the gear oil.
Drive pinion to ring gear backlash
incorrect.Adjust the backlash.
Worn or chipped ring gear, pinion
gear or side gear.Replace the ring gear, pinion gear or
side gear.
Pinion shaft bearing worn.Replace the pinion shaft bearing.
Wheel bearing worn.Replace the wheel bearing.
Differential bearing loose or worn.Tighten or replace.
Wanders and PullsWheel bearing preload too tight.Adjust the wheel bearing preload.
Incorrect front alignment.Adjust the front alignment.
Steering linkage loose or worn.Tighten or replace.
Steering gear out of adjustment.Adjust or replace the steering gear.
Tire worn or improperly inflated.Adjust the inflation or replace.
Front or rear suspension parts loose
or broken.Tighten or replace.
Front Wheel ShimmyWheel bearing worn or improperly
adjusted.Adjust or replace.
Incorrect front alignment.Adjust the front alignment.
Worn ball joint or bush.Replace the ball joint or bush.
Steering linkage loose or worn.Tighten or replace.
Steering gear out of adjustment.Tighten or replace.
Tire worn or improperly inflated.Replace or adjust the inflation.
Shock absorber worn.Replace the shock absorber.

4C–22
DRIVE SHAFT SYSTEM
Front Drive Shaft Joint
Front Drive Shaft Joints Replace-
ment
Refer to Front Drive Axle Assembly Replacement in
this section, and refer to Front Hub and Disc in
Suspension section.
Front Hub Bearing Preload Check
Check the hub bearing preload at the wheel pin.
New bearing and New oil seal
Preload: 20 – 25 N (2.0 – 2.5 kg/4.4–5.5 lb)
New bearing and New oil seal
Preload: 12 –18 N (1.2 – 1.8 kg/2.6–4.0 lb)
411RS001
Inspection Of Shift On The Fly System
Gear Oil
412RT002
1. Open filler plug and make sure that the oil is up to the
plug port.
If the level oil is low, replenish with gear oil GL–5
grade.
2. Tighten the filler plug to specified torque.
Torque: 7.8 Nꞏm (7.9 kgꞏcm/58 lb in)

6A–5
ENGINE MECHANICAL
4. Engine Lacks Compression
Condition
Possible causeCorrection
Engine lacks compressionSpark plug loosely fitted or spark
plug gasket defectiveTighten to specified torque or replace
gasket
Valve timing incorrectAdjust
Cylinder head gasket defectiveReplace gasket
Valve incorrectly seatedLap valve
Valve stem seizedReplace valve and valve guide
Valve spring weakened or brokenReplace
Cylinder or piston rings wornOverhaul engine
Piston ring seizedOverhaul engine.
Engine Compression Test Procedure
1. Start and run the engine until the engine reaches
normal operating temperature.
2. Turn the engine off.
3. Remove all the spark plugs.
4. Remove ignition coil fuse (15A) and disable the
ignition system.
5. Remove the fuel pump relay from the relay and fuse
box.
6. Engage the starter and check that the cranking speed
is approximately 300 rpm.7. Install cylinder compression gauge into spark plug
hole.
8. With the throttle valve opened fully, keep the starter
engaged until the compression gage needle reaches
the maximum level. Note the reading.
9. Repeat the test with each cylinder.
If the compression pressure obtained falls below the
limit, engine overhaul is necessary.
Limit; 1000 kPa (145 psi)