Subaru Forester AWD System 1999 2000 (10) PDF

2. Rear Differential
Symptom Possible cause Remedy
1. Oil leakage (1) Worn, scratched, or incorrectly
seated front or side oil seal. Scored,
battered, or excessively worn sliding sur-
face of companion flange.
Repair or replace.
(2) Clogged or damaged air breather. Clean, repair or replace.
(3) Loose bolts on differential spindle or
side retainer, or incorrectly fitted O-ring.
Tighten bolts to specified torque.
Replace O-ring.
(4) Loose rear cover attaching bolts or
damaged gasket.
Tighten bolts to specified torque.
Replace gasket and apply liquid packing.
(5) Loose oil filler or drain plug. Retighten and apply liquid packing.
(6) Wear, damage or incorrectly fitting for
spindle, side retainer and oil seal.
Repair or replace.
2. Seizure
NOTE:
Seized or damaged parts should be
replaced, and also other parts should be
thoroughly checked for any defect and
should be repaired or replaced as
required.
(1) Insufficient backlash for hypoid gear. Readjust or replace.
(2) Excessive preload for side, rear, or
front bearing.
Readjust or replace.
(3) Insufficient or improper oil used. Replace seized part and fill with speci-
fied oil to specified level.
3. Damage
NOTE:
Damaged parts should be replaced, and
also other parts should be thoroughly
checked for any defect and should be
repaired or replaced as required.
(1) Improper backlash for hypoid gear. Replace.
(2) Insufficient or excessive preload for
side, rear, or front bearing.
Readjust or replace.
(3) Excessive backlash for differential
gear.
Replace gear or thrust washer.
(4) Loose bolts and nuts such as crown
gear bolt.
Retighten.
(5) Damage due to overloading. Replace.
4. Noises when starting or shifting
gears
NOTE:
Noises may be caused by differential
assembly, universal joint, wheel bearing,
etc. Find out what is actually making
noise before disassembly.
(1) Excessive backlash for hypoid gear. Readjust.
(2) Excessive backlash for differential
gear.
Replace gear or thrust washer.
(3) Insufficient preload for front or rear
bearing.
Readjust.
(4) Loose drive pinion nut. Tighten to specified torque.
(5) Loose bolts and nuts such as side
bearing retainer attaching bolt.
Tighten to specified torque.
5. Noises when cornering (1) Damaged differential gear. Replace.
(2) Excessive wear or damage of thrust
washer.
Replace.
(3) Broken pinion mate shaft. Replace.
(4) Seized or damaged side bearing. Replace.
6. Gear noises
NOTE:
Since noises from engine, muffler,
transmission, propeller shaft, wheel
bearings, tires, and body are sometimes
mistaken for noises from differential
assembly, be careful in checking them.
Inspection methods to locate noises
include coasting, accelerating, cruising,
and jacking-up all four wheels. Perform
these inspections according to condition
of trouble. When listening to noises, shift
gears into four wheel drive and fourth
speed position, trying to pick up only dif-
ferential noise.
(1) Improper tooth contact of hypoid
gear.
Readjust or replace hypoid gear set.
(2) Improper backlash for hypoid gear. Readjust.
(3) Scored or chipped teeth of hypoid
gear.
Replace hypoid gear set.
(4) Seized hypoid gear. Replace hypoid gear set.
(5) Improper preload for front or rear
bearings.
Readjust.
(6) Seized, scored, or chipped front or
rear bearing.
Replace.
(7) Seized, scored, or chipped side bear-
ing.
Replace.
(8) Vibrating differential carrier. Replace.
34
3-4 [K200] DIAGNOSTICS
2. Rear Differential

Subaru Forester AWD System 1999 2000 (10) Summary of Content

2. Rear DifferentialSymptom Possible cause Remedy1. Oil leakage (1) Worn, scratched, or incorrectlyseated front or side oil seal. Scored,battered, or excessively worn sliding sur-face of companion flange.Repair or replace.(2) Clogged or damaged air breather. Clean, repair or replace.(3) Loose bolts on differential spindle orside retainer, or incorrectly fitted O-ring.Tighten bolts to specified torque.Replace O-ring.(4) Loose rear cover attaching bolts ordamaged gasket.Tighten bolts to specified torque.Replace gasket and apply liquid packing.(5) Loose oil filler or drain plug. Retighten and apply liquid packing.(6) Wear, damage or incorrectly fitting forspindle, side retainer and oil seal.Repair or replace.2. SeizureNOTE:Seized or damaged parts should bereplaced, and also other parts should bethoroughly checked for any defect andshould be repaired or replaced asrequired.(1) Insufficient backlash for hypoid gear. Readjust or replace.(2) Excessive preload for side, rear, orfront bearing.Readjust or replace.(3) Insufficient or improper oil used. Replace seized part and fill with speci-fied oil to specified level.3. DamageNOTE:Damaged parts should be replaced, andalso other parts should be thoroughlychecked for any defect and should berepaired or replaced as required.(1) Improper backlash for hypoid gear. Replace.(2) Insufficient or excessive preload forside, rear, or front bearing.Readjust or replace.(3) Excessive backlash for differentialgear.Replace gear or thrust washer.(4) Loose bolts and nuts such as crowngear bolt.Retighten.(5) Damage due to overloading. Replace.4. Noises when starting or shiftinggearsNOTE:Noises may be caused by differentialassembly, universal joint, wheel bearing,etc. Find out what is actually makingnoise before disassembly.(1) Excessive backlash for hypoid gear. Readjust.(2) Excessive backlash for differentialgear.Replace gear or thrust washer.(3) Insufficient preload for front or rearbearing.Readjust.(4) Loose drive pinion nut. Tighten to specified torque.(5) Loose bolts and nuts such as sidebearing retainer attaching bolt.Tighten to specified torque.5. Noises when cornering (1) Damaged differential gear. Replace.(2) Excessive wear or damage of thrustwasher.Replace.(3) Broken pinion mate shaft. Replace.(4) Seized or damaged side bearing. Replace.6. Gear noisesNOTE:Since noises from engine, muffler,transmission, propeller shaft, wheelbearings, tires, and body are sometimesmistaken for noises from differentialassembly, be careful in checking them.Inspection methods to locate noisesinclude coasting, accelerating, cruising,and jacking-up all four wheels. Performthese inspections according to conditionof trouble. When listening to noises, shiftgears into four wheel drive and fourthspeed position, trying to pick up only dif-ferential noise.(1) Improper tooth contact of hypoidgear.Readjust or replace hypoid gear set.(2) Improper backlash for hypoid gear. Readjust.(3) Scored or chipped teeth of hypoidgear.Replace hypoid gear set.(4) Seized hypoid gear. Replace hypoid gear set.(5) Improper preload for front or rearbearings.Readjust.(6) Seized, scored, or chipped front orrear bearing.Replace.(7) Seized, scored, or chipped side bear-ing.Replace.(8) Vibrating differential carrier. Replace.343-4 [K200] DIAGNOSTICS2. Rear Differential