engine ISUZU TF SERIES 2004 User Guide

4B-6 REAR AXLE

RECOMMENDED LIQUID GASKET

Type Brand Name Manufacture Remarks

RTV*
Silicon Base ThreeBond 1207B
ThreeBond 1207C

ThreeBond 1215
Three Bond
Three Bond

Three Bond
For Engine Repairs


For Axle Case
Repairs, T/M
Water Base ThreeBond 1141E Three Bond For Engine Repairs

Solvent ThreeBond 1104
BelcoBond 4
BelcoBond 401
BelcoBond 402 Three bond
Isuzu
Isuzu
Isuzu
For Engine Repairs
Anaerobic LOCTITE 515
LOCTITE 518 Loctite
Loctite All
* RTV : Room Temperature Vulcanizer
Note :
1. It is very important that the liquid gaskets listed
above or their exact equivalent be used on the
vehicle.
2. Be careful to use the specified amount of liquid
gasket.
Follow the manufacture's instructions at all
times.

3. Be absolutely sure to remove all lubricants and
moisture from the connecting surfaces before
applying the liquid gasket.
The connecting surfaces must be perfectly dry.
4. LOCTITE 515 and LOCTITE 518 harden upon
contact with a metal surface.
Do not apply LOCTITE 515 or LOCTITE 518
between two metal surfaces having a clearance
of greater than 0.25 mm (0.01 in). Poor
adhesion will result.



RECOMMENDED THREAD LOCKING AGENTS

LOCTITE Type LOCTITE Color Application Steps

LOCTITE 242
Blue 1. Completely remove all lubricant and moisture from the bolts and
the female threaded surfaces of the parts to be joined.

The surfaces must be perfectly dry.

LOCTITE 262

Red 2. Apply LOCTITE to the bolts.


LOCTITE 270

Green

LOCTITE 271

Red
3. Tighten the bolts to the specified torque.
4. Wait at least one hour before continuing the installation procedure.

REAR AXLE 4B-7

REAR AXLE ASSEMBLY
General Description
A03R300001

The rear axle assembly is of the semi–floating type in
which the vehicle weight is carried on the axle
housing .
The center line of the pinion gear is below the center
line of the ring gear (hypoid drive).
All parts necessary to transmit power from the
propeller shaft to the rear wheels are enclosed in a
banjo type axle housing.
The 220 mm (8.6 in) ring gear rear axle uses a
conventional ring and pinion gear set to transmit the
driving force of the engine to the rear wheels. This
gear set transfers this driving force at a 90 degree
angle from the propeller shaft to the drive shafts.
The axle shafts are supported at the wheel end of the
shaft by a double tapered roller bearing.
The pinion gear is supported by two tapered roller
bearings. The pinion depth is set by a shim pack
located between the gear end of the pinion and the
roller bearing that is pressed onto the pinion. The
pinion bearing preload is set by crushing a collapsible
spacer between the bearings in the axle housing.
The ring gear is bolted onto the differential cage with
12 bolts.
The differential cage is supported in the axle housing
by two tapered roller bearings. The differential and ring
gear are located in relationship to the pinion by using
selective shims and spacers between the bearing and
the differential cage. To move the ring gear, shims are
deleted from one side and an equal amount are added
to the other side. These shims are also used to
preload the bearings which are pressed onto the
differential cage. Two bearing caps are used to hold
the differential into the rear axle housing.
The differential is used to allow the wheels to turn at
different rates of speed while the rear axle continues
to transmit the driving force. This prevents tire
scuffing when going around corners and prevents
premature wear on internal axle parts.
The rear axle is sealed with a pinion seal, a seal at
each axle shaft end, and by a liquid gasket between
the differential carrier and the axle housing

REAR AXLE 4B-43

TROUBLESHOOTING
Refer to this Section to quickly diagnose and repair
rear axle problems.
Each troubleshooting chart has three headings
arranged from left to right.
(1) Checkpoint
(2) Trouble Cause
(3) Countermeasure
This Section is divided into five sub-sections:
1. Abnormal Rear Axle Noise
1) Noise when the engine is driving the vehicle
2) Noise when the vehicle is coasting
3) Intermittent noise
4) Noise when the vehicle is turning
5) Constant noise
2. Vibration
3. Oil Leakage
1) Differential carrier leakage
2) Axle case leakage
3) Axle case to inside hub leakage
4) Axle case to inside brake drum leakage
4. Power Not Being Transmitted to the Wheels
(Propeller Shaft Operation is Normal)

4B-44 REAR AXLE

1. ABNORMAL REAR AXLE NOISE
1) Noise when the Engine is Driving the Vehicle

Checkpoint Trouble Cause Countermeasure

Replenish the gear oilInsufficient gear oil NG
Differential side bearingAdjust the differential side
bearing preload
Replace the drive pinion
bearings
Adjust the drive pinion bearing
preload
Replace the gear oil
Loose differential side
bearings
Worn drive pinion bearings
Loose drive pinion bearings
Wrong or poor grade gear oil
Drive pinion to ring gear
backlash
Drive pinion end play
Adjust the backlashToo much or too little backlash
Continued on the next pageOK OK
NG NG NG NG NG
OK
OK
Rear axle gear oil
Replace the differential side
bearingsWorn differential side bearings NG

FRONT WHEEL DRIVE 4C1-3
MAIN DATA AND SPECIFICATIONS
FRONT AXLE AND DIFFERENTIAL
Ring gear size mm (in) 194 (7.6)
Axle tube
Type It consists of the duce, a cast iron housing and the Axle tube.
Gear type Hypoid
Gear ratio (to 1) 4.100, 4.300, 4.555, 4.777, 5125
Differential type Two pinion
Specified gear oil (APL grade) GL-5
Oil capacity liter 1.4
(US/UK gal.) (0.4/0.33)
Axle shaft type Constant velocity joint (Birfield joint type and double offset joint).


FRONT PROPELLER SHAFT mm(in)
4

4 Model
Engine Model 4JA1-T(L) 4JA1-TC 4JH1-TC C24SE 6VE1
Transmission Type 5M/T (MUA) 5M/T
(MUA) 4A/T 5M/T
(MUA) 5M/T
(MUA) 4A/T
Front Axle 194 mm










Outside Diameter mm 40 40 40 40 40 40
(in) (1.57) (1.57) (1.57) (1.57) (1.57) (1.57)
Inside Diameter mm 32 32 32 32 32 32
(in) (1.26) (1.26) (1.26) (1.26) (1.26) (1.26)
Length (L) mm 607 607 676 586 586 607
(in) (23.90) (23.90) (26.61) (23.07) (23.07) (23.90)
Fix Bolt Size T/F M10 M10 M10 M10 M10 M10
Axle M10 M10 M10 M10 M10 M10

4C1-6 FRONT WHEEL DRIVE
RECOMMENDED LIQUID GASKET

Type Brand Name Manufacture Remarks

RTV*
Silicon Base ThreeBond 1207B
ThreeBond 1207C

ThreeBond 1215
Three Bond
Three Bond

Three Bond
For Engine Repairs


For Axle Case
Repairs, T/M
Water Base ThreeBond 1141E Three Bond For Engine Repairs

Solvent ThreeBond 1104
BelcoBond 4
BelcoBond 401
BelcoBond 402 Three bond
Isuzu
Isuzu
Isuzu
For Engine Repairs
Anerobic LOCTITE 515
LOCTITE 518 Loctite
Loctite All
* RTV : Room Temperature Vulcanizer

Note :
1. It is very important that the liquid gaskets listed above or their exact equivalent be used on the vehicle.
2. Be careful to use the specified amount of liquid gasket.
Follow the manufacture's instructions at all times.
3. Be absolutely sure to remove all lubricants and moisture from the connecting surfaces before applying
the liquid gasket.
The connecting surfaces must be perfectly dry.
4. LOCTITE 515 and LOCTITE 518 harden upon contact with a metal surface.
Do not apply LOCTITE 515 or LOCTITE 518 between two metal surfaces having a clearance of greater
than 0.25 mm (0.01 in). Poor adhesion will result.

RECOMMENDED THREAD LOCKING AGENTS

LOCTITE Type LOCTITE Color Application Steps

LOCTITE 242
Blue 1. Completely remove all lubricant and moisture from the bolts and
the female threaded surfaces of the parts to be joined.
The surfaces must be perfectly dry.

LOCTITE 262

Red 2. Apply LOCTITE to the bolts.


LOCTITE 270

Green

LOCTITE 271

Red
3. Tighten the bolts to the specified torque.
4. Wait at least on hour before continuing the installation procedure.

BRAKE CONTROL SYSTEM 5A-13

Connector List
No. Connector face No. Connector face
B-23
Green
Meter-A C-44
WhiteStop Light Switch
B-24
Green
Meter-B C-53
OrangeABS Sensor Front-RH
B-48
Black
G-sensor C-54
OrangeABS Sensor Front-LH
B-54
White
I2 C-67
BlackEHCU
B-56
White
J/B I4 C-107
WhiteJ/B E2
B-58
Black
Data Link Connector C-108
WhiteJ/B E1
B-62
White
Ignition Switch (IGSUB : G1) C-109
SilverBody-LH ; Ground
B-63
White
Ignition Switch (IGSUB : G2) F-4
Gray ABS Sensor Rear
C-2
Silver
Engine Room-RH ; ground H-6
WhiteEngine Room ~ INST
C-36
Silver
Engine Room-LH ; Ground H-7
WhiteEngine Room ~ INST

5A-14 BRAKE CONTROL SYSTEM


No. Connector face No. Connector face
H-15
White
Engine Room ~ Chassis


H-18
White
Engine Room ~ INST


P-2
Silver
Relay & Fuse Box


P-6
Silver
Body Earth (Ground)


P-10
Silver
Engine Ground


R-15
Black
2-4WD Control Unit

BRAKE CONTROL SYSTEM 5A-19

System Components
Electronic Hydraulic Control Unit (EHCU), four Wheel
Speed Sensors, two Warning Lamps, and G-sensor.

Electronic Hydraulic Control Unit (EHCU)

The EHCU consists of ABS control circuits, fault
detector, and a fail-safe. It drives the EHCU according
to the signal from each sensor, cancelling ABS to return
to normal braking when a malfunction has occurred in
the ABS.
The EHCU has a self-diagnosing function which can
indicate faulty circuits during diagnosis.
The EHCU is mounted on the engine compartment rear
left side. It consists of a motor, solenoid valves fail safe
relay.
Solenoid Valves: Reduces or holds the caliper fluid
pressure for each front brake or both rear brakes
according to the signal sent from the EHCU.
Buffer chamber: Temporarily holds the brake fluid that
returns from the front and rear brake so that pressure
of front brake can be reduced smoothly.
Motor: Drives the pump according to the signal from
EHCU.
Fail safe Relay: When failure occurs in ABS.
The power supply to solenoid Valve is cut.

ABS Warning Lamp


825L300001
Vehicles equipped with the Anti-lock Brake System
have an amber “ABS” warning lamp in the instrument
panel. The “ABS” warning lamp will illuminate if a
malfunction in the Anti-lock Brake System is detected
by the Electronic Hydraulic Control Unit (EHCU). In
case of an electronic malfunction, the EHCU will turn
“ON” the “ABS” warning lamp and disable the anti-lock
braking function.

The “ABS” warning lamp will turn “ON” for
approximately three seconds after the ignition switch is
to the “ON” position.
If the “ABS” warning lamp stays “ON” after the ignition
switch is the “ON” position, or comes “ON” and stays
“ON” while driving, the Anti-lock Brake System should
be inspected for a malfunction according to the
diagnosis procedure.

Wheel Speed Sensor (WSS)
It consists of a sensor and a rotor. The sensor is
attached to the knuckle on the front wheels and to the
rear wheels.
The rotor is press-fit in the axle shaft.

G-Sensor
The G-sensor detects the vehicle deceleration speed
and sends a signal to the EHCU. In 4WD operation, all
four wheels may be decelerated in almost the same
phase, since all wheels are connected mechanically.
This tendency is noticeable particularly on roads with
low friction coefficient, and the ABS control is adversely
affected.
The G-sensor judges whether the friction coefficient of
road surface is low or high, and changes the EHCU's
operating system to ensure ABS and EBD control.

Normal and Anti-lock Braking
Under normal driving conditions, the Anti-lock Brake
System functions the same as a standard power
assisted brake system. However, with the detection of
wheel lock-up, a slight bump or kick-back will be felt in
the brake pedal. This pedal “bump” will be followed by a
series of short pedal pulsations which occurs in rapid
succession. The brake pedal pulsation will continue
until there is no longer a need for the anti-lock function
or until the vehicle is stopped. A slight ticking or
popping noise may be heard during brake applications
when the anti-lock features is being used.
When the anti-lock feature is being used, the brake
pedal may rise even as the brakes are being applied.
This is also normal. Maintaining a constant force on
the pedal will provide the shortest stopping distance.

BRAKE CONTROL SYSTEM 5A-21

Computer System Service Precautions
The Anti-lock Brake System and Electronic Brake-force
Distribution interfaces directly with the Electronic
Hydraulic Control Unit (EHCU) which is a control
computer that is similar in some regards to the Engine
Control Module. These modules are designed to
withstand normal current draws associated with vehicle
operation. However, care must be taken to avoid
overloading any of the EHCU circuits. In testing for
opens or shorts, do not ground or apply voltage to any
of the circuits unless instructed to do so by the
appropriate diagnostic procedure. These circuits should
only be tested with a high impedance multimeter
5-8840-0366-0 or special tools as described in this
section. Power should never be removed or applied to
any control module with the ignition in the “ON”
position.
Before removing or connecting battery cables, fuses or
connectors, always turn the ignition switch to the “OFF”
position.

General Service Precautions
The following are general precautions which should be
observed when servicing and diagnosing the Anti-lock
Brake System and/or other vehicle systems. Failure to
observe these precautions may result in Anti-lock Brake
System and Electronic Brake-force Distribution
damage.
 If welding work is to be performed on the vehicle
using an electric arc welder, the EHCU and valve
block connectors should be disconnected before
the welding operation begins.
 The EHCU and valve block connectors should
never be connected or disconnected with the
ignition “ON”.
Note:
 If only rear wheels are rotated using jacks or drum
tester, the system will diagnose a speed sensor
malfunction and the “ABS and Brake” warning lamp
will illuminate. But actually no trouble exists. When
the DTC is not detected and the ABS and BRAKE
warning lamp is on, “How to erase code” is
performed and a ABS and BRAKE warning lamp
are off.
If the battery has been discharged
The engine may stall if the battery has been completely
discharged and the engine is started via jumper cables.
This is because the Anti-lock Brake System (ABS) and
Electronic Brake-force Distribution (EBD) System
requires a large quantity of electricity. In this case, wait
until the battery is recharged, or set the ABS and EBD
to a non-operative state by removing the fuse for the
ABS. After the battery has been recharged, stop the
engine and install the ABS fuse. Start the engine again,
and confirm that the ABS warning Lamp does not light.
Note on Intermittents
As with virtually any electronic system, it is difficult to
identify an intermittent failure. In such a case
duplicating the system malfunction during a test drive or
a good description of vehicle behavior from the
customer may be helpful in locating a “most likely”
failed component or circuit. The symptom diagnosis
chart may also be useful in isolating the failure. Most
intermittent problems are caused by faulty electrical
connections or wiring. When an intermittent failure is
encountered, check suspect circuits for:
 Suspected harness damage.
 Poor mating of connector halves or terminals not
fully seated in the connector body (backed out).
 Improperly formed or damaged terminals.

Test Driving ABS Complaint Vehicles
In case that there has been an abnormality in the
lighting pattern of “ABS” warning lamp, the fault can be
located in accordance with the “DIAGNOSIS BY “ABS”
WARNING LAMP ILLUMINATION PATTERN”. In case
of such trouble as can be detected by the driver as a
vehicle symptom, however, it is necessary to give a test
drive following the test procedure mentioned below,
thereby reproducing the symptom for trouble diagnosis
on a symptom basis:
1.
Start the engine and make sure that the “ABS” W/L
goes OFF. If the W/L remains ON, it means that
the Diagnostic Trouble Code (DTC) is stored.
Therefore, read the code and locate the fault.
Note: The DTC cannot be cleared if the vehicle speed
does not exceed about 6km/h (4mph) at DTC, even
though the repair operation is completed.
2. Start the vehicle and accelerate to about 30 km/h
(19 mph) or more.
3. Slowly brake and stop the vehicle completely.
4. Then restart the vehicle and accelerate to about 40
km/h (25 mph) or more.
5. Brake at a time so as to actuate the ABS and stop
the vehicle.
6. Be cautious of abnormality during the test. If the
W/L is actuated while driving, read the DTC and
locate the fault.
7. If the abnormality is not reproduced by the test,
make best efforts to reproduce the situation
reported by the customer.
8. If the abnormality has been detected, repair in
accordance with the “SYMPTOM DIAGNOSIS” .
Note:

Be sure to give a test drive on a wide, even road
with a small traffic.
 If an abnormality is detected, be sure to suspend
the test and start trouble diagnosis at once.