4A1–1 DIFFERENTIAL (FRONT)
DRIVELINE/AXLE
CONTENTS
Differential (Front) 4A1. . . . . . . . . . . . . . . . . . . . . . .
Differential (Rear/220mm) 4A2A. . . . . . . . . . . . . . . .
Differential (Rear/244mm) 4A2B. . . . . . . . . . . . . . . .
Driveline Control System (Shift on the Fly) 4B1. . Driveline Control System (TOD) 4B2. . . . . . . . . . .
Driveshaft System 4C. . . . . . . . . . . . . . . . . . . . . . .
Transfer Case (Standard Type) 4D1. . . . . . . . . . .
Transfer Case (TOD) 4D2. . . . . . . . . . . . . . . . . . . .
DIFFERENTIAL (FRONT)
CONTENTS
Service Precaution 4A1–1. . . . . . . . . . . . . . . . . . . . . .
Front Drive Axle 4A1–2. . . . . . . . . . . . . . . . . . . . . . . . .
Diagnosis 4A1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pinion Shaft Oil Seal 4A1–3. . . . . . . . . . . . . . . . . . . . .
Pinion Shaft Oil Seal and Associated Parts 4A1–3
Removal 4A1–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4A1–4. . . . . . . . . . . . . . . . . .
Installation 4A1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Drive Axle Assembly 4A1–5. . . . . . . . . . . . . . .
Front Drive Axle Assembly and
Associated Parts 4A1–5. . . . . . . . . . . . . . . . . . . . . .
Removal 4A1–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation 4A1–7. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Assembly 4A1–9. . . . . . . . . . . . . . . . . . . .
Disassembled View 4A1–9. . . . . . . . . . . . . . . . . . . .
Disassembly 4A1–9. . . . . . . . . . . . . . . . . . . . . . . . . .
Reassembly 4A1–12. . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Cage Assembly 4A1–21. . . . . . . . . . . . . . .
Disassembled View 4A1–21. . . . . . . . . . . . . . . . . . . .
Disassembly 4A1–21. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4A1–22. . . . . . . . . . . . . . . . . .
Reassembly 4A1–23. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4A1–25. . . . . . . . . . .
Special Tools 4A1–28. . . . . . . . . . . . . . . . . . . . . . . . . .
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 REFORMING 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 specification. Following these
instructions can help you avoid damage to parts and
systems.
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.
4A1–3 DIFFERENTIAL (FRONT)
Pinion Shaft Oil Seal
Pinion Shaft Oil Seal and Associated Parts
415RW015
Legend
(1) Flange Nut
(2) Flange(3) Oil Seal
(4) Outer Bearing
(5) Collapsible Spacer
Removal
1. Raise the vehicle and support it at the frame.
The hoist must remain under the front axle housing.
2. Drain the front axle oil by loosening the drain plug(1).
412RS001
