air condition OPEL FRONTERA 1998 User Guide
Page 439 of 6000
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. 
Page 441 of 6000
DIFFERENTIAL (FRONT) 4A1–4
3. Remove  the  front  propeller  shaft.  Refer  to  Front
Propeller Shaft in this section.
4. Remove  flange  nut  by  using  pinion  flange  holder
5–8840–2157–0.
425RW045
5. Remove flange.
6. Remove oil seal.
7. Remove  outer  bearing  by  using  remover
5–8840–2323–0.
415RW022
8. Remove collapsible spacer.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal conditions are
found through inspection.
Check the following parts:
1. Seal surface of the pinion.
2. Cage bore for burns.
Installation
1. Install  collapsible  spacer.  Discard  the  used
collapsible spacer and install a new one.
2. Install outer bearing.
NOTE: Do not drive in, but just temporarily set in the outer
bearing  by  hand,  which  should  be  indirectly  pressed  in
finally by tightening the flange nut.
3. Install oil seal, use oil seal installer 9–8522–1275–0 to
install  a  new  oil  seal  that  has  been  soaked  in  axle
lubricant.
415RW021
4. Install flange.
5. Install  flange  nut,  refer  to  Differential  Assembly    for
flange nut reassembly in this section.
NOTE: Discard the used nut and install a new one. 
Page 459 of 6000
DIFFERENTIAL (FRONT) 4A1–22
4. Remove the cross pin, using a soft metal rod and a
hammer.
425RS043
5. Remove pinion gear.
6. Remove side gear.
7. Remove thrust washer.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal conditions are
found through inspection.
Check the following parts:
1. Ring gear, pinion gear
2. Bearing
3. Side gear, pinion gear, cross pin
4. Differential cage, carrier
5. Thrust washer
6. Oil seal
Ring gear replacement:
1. The  ring  gear  should  always  be  replaced  with  the
drive pinion as a set.
2. Clean  the  ring  gear  threaded  holes  to  remove  the
locking agent.
3. When installing the ring gear, apply LOCTITE 271 or
equivalent  to  all  the  threaded  area  and  half  of  the
unthreaded area of the bolt.
4. Discard used bolts and install new ones.
Torque: 108 Nꞏm (11kgꞏm/80 lb ft)5. Tighten  the  fixing  bolts  in  a  diagonal  sequence  as
illustrated.
415RS016
Clearance between the differential pinion
and the cross pin measurement:
Standard: 0.06 – 0.12 mm (0.002–0.005 in)
Limit: 0.2 mm (0.008 in)
425RS045 
Page 470 of 6000
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. 
Page 474 of 6000
DIFFERENTIAL (REAR 220mm)
4A2A–7
3. Remove flange nut and washer by using pinion flange
holder  5–8840–2157–0  after  raising  up  its  staked
parts completely.
415RW028
4. Remove flange.
5. Remove oil seal.
6. Remove  outer  bearing  by  using  remover
5–8840–2323–0.
425RW066
7. Remove collapsible spacer.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal conditions are
found through inspection.
Check the following parts:
1. Seal surface of the pinion.
2. Cage bore for burns.
Installation
1. Install collapsible spacer, discard the used collapsible
spacer and install a new one.
2. Install outer bearing.
NOTE: Do not drive in, but just temporarily set in the outer
bearing  by  hand,  which  should  be  indirectly  pressed  in
finally by tightening the flange nut.
3. By using the seal installer 5–8840–2165–0, install a
new oil seal (1) that has grease on seal lip.
425RW050
4. Install flange.
5. Install  flange  nut  and  washer.  Refer  to  Differential
Assembly in this section for flange nut reassembly.
NOTE: Discard the used nut and install a new one. 
Page 489 of 6000
4A2A–22
DIFFERENTIAL (REAR 220mm)
4. Remove the cross pin, using a soft metal rod and a
hammer.
425RS043
5. Remove pinion gear.
6. Remove side gear.
7. Remove thrust washer.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal conditions are
found through inspection.
Check the following parts:
1. Ring gear, pinion gear
2. Bearing
3. Side gear, pinion gear, cross pin
4. Differential cage, carrier
5. Thrust washer
6. Oil seal
Ring gear replacement:
1. The  ring  gear  should  always  be  replaced  with  the
drive pinion as a set.
2. Clean  the  ring  gear  threaded  holes  to  remove  the
locking agent.
3. When installing the ring gear, apply LOCTITE 271 or
equivalent  to  all  the  threaded  area  and  half  of  the
unthreaded area of the bolt.
4. Discard used bolts and install new ones.
Torque: 108 Nꞏm (11.0kgꞏm/80 lb ft)5. Tighten  the  fixing  bolts  in  a  diagonal  sequence  as
illustrated.
415RW036
Clearance between the differential pinion
and the cross pin measurement:
Standard: 0.06 – 0.12 mm (0.002–0.005 in)
Limit: 0.2 mm (0.008 in)
425RS045 
Page 493 of 6000
4A2A–26
DIFFERENTIAL (REAR 220mm)
Disassembly
1. Using special tool, 5–8840–2381–0, grip it with a vice,
and set the differential.
425RS054
2. Gradually and evenly loosen the 4 fixing screws of the
differential cages A and B.
425RS055
3. Remove Differential cage A.
4. Remove Thrust washer. 
5. Remove Spring disc.
NOTE: When removing the spring disc, friction disc, and
friction  plate,  place  them in order  for  clear distinction  of
left and right use.
6. Remove Spring disc.7. Remove Friction plate. 
8. Remove Friction disc.
9. Remove Friction plate.
10. Remove Friction disc.
11. Remove Pressure ring. 
12. Remove Side gear.
13. Remove Pinion and pinion shaft.
14. Remove Side gear.
15. Remove Pressure ring.
16. Remove Friction disc.
17. Remove Friction plate.
18. Remove Friction disc.
19. Remove Friciton plate.
20. Remove Spring disc.
21. Remove Spring disc.
22. Remove Thrust washer.
23. Remove Differential cage B.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage,  corrosion  or  any  other  abnormal  condition  is
found through inspection.
Visual check
Check the following parts for wear, damage, noise or any
other abnormal conditions.
Friction disc, friction plate and spring disc
425RS056
Legend
(1) Sliding surfaces
(2) Projections 
Page 506 of 6000
DIFFERENTIAL (REAR 244mm)
4A2B–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. 
Page 510 of 6000
DIFFERENTIAL (REAR 244mm)
4A2B–7
3. Remove flange nut and washer by using pinion flange
holder  5–8840–0133–0  after  raising  up  its  staked
parts completely.
415RW040
4. Remove flange.
5. Remove oil seal.
6. Remove  outer  bearing  by  using  remover
5–8840–2323–0.
425RW066
7. Remove collapsible spacer.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal conditions are
found through inspection.
Check the following parts:
1. Seal surface of the pinion.
2. Cage bore for burns.
Installation
1. Install collapsible spacer, discard the used collapsible
spacer and install a new one.
2. Install outer bearing.
NOTE: Do not drive in, but just temporarily set in the outer
bearing  by  hand,  which  should  be  indirectly  pressed  in
finally by tightening the flange nut.
3. By using the seal installer 5–8840–2165–0, install a
new oil seal (1) that has grease on seal lip.
425RW050
4. Install flange.
5. Install  flange  nut  and  washer.  Refer  to  Differential
Assembly in this section for flange nut reassembly.
NOTE: Discard the used nut and install a new one. 
Page 524 of 6000
DIFFERENTIAL (REAR 244mm)
4A2B–21
Disassembly
1. Remove bolt.
2. Remove ring gear.
3. Remove lock pin using a small drift.
425RS042
4. Remove  the  differential  shaft  by  using  a  hard  metal
rod and a hammer.
425RS043
5. Remove pinion mate gear and thrust washer.
6. Remove side gear and thrust washer.
Inspection and Repair
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal conditions are
found through inspection.
Check the following parts:
Ring gear, pinion gear
Bearing
Side gear, pinion mate gear, differential shaft
Differential cage, carrier
Thrust washer
Oil seal
Ring gear replacement:
1. The  ring  gear  should  always  be  replaced  with  the
drive pinion as a set.
2. Discard used bolts and install new ones.
3. Tighten  the  fixing  bolts  in  a  diagonal  sequence  as
illustrated.
Torque: 177Nꞏm (18.0kgꞏm/130 lb ft)
425RW033
Reassembly
425RS048
1. Install side gear with thrust washer.