tires ISUZU TF SERIES 2004 Owner's Manual

WHEELS AND TIRES 3E-7

DISASSEMBLY and REASSEMBLY


Disassembly Steps
(for Alumi models)
1. Wheel cap
2. Wheel nut
3. Wheel and tire assembly
4. Tire assembly
(for Steel models)
1. Wheel nut
2. Wheel cap
3. Wheel and tire assembly
4. Tire assembly
Reassembly Steps
(for Alumi models)
4. Tire assembly
3. Wheel and tire assembly
2. Wheel nut
1. Wheel cap
(for Steel models)
4 Tire assembly
3. Wheel and tire assembly
2. Wheel cap
1. Wheel nut

3E-8 WHEELS AND TIRES

INSPECTION AND REPAIR
Make necessary correction or parts replacement if wear, damage or any other abnormal conditions are found
through inspection.




Visual Check
Inspect all disassembled parts for wear, damage or other
abnormal conditions.




Measure Wheel Runout
mm
Wheel Type Radial Lateral
14 inch Steel
15 inch Steel
16 inch Steel Less than 1.0 Less than 1.0
15 inch Alumi
16 inch Alumi Less than 0.4 Less than 0.55
If the measured value exceed the specified limit, the wheel
must be replaced.




Balancing Wheel and Tire
On-vehicle Balancing

On-Vehicle balancing methods very with equipment and tool
manufacturers. Be sure to follow each manufacturer’s
instructions during balancing operation.
Off- vehicle Balancing

Most electronic off-vehicle balancers are more accurate than
the on-vehicle spin balancers. They are easy to use and give a
dynamic balance. Although they do not correct for drum or
disc unbalance (as on-vehicle spin balancing does), they are
very accurate.

WHEELS AND TIRES 3E-9


Important Operations
1. Tire Assembly
Align the match mark (approx. 10mm diameter paint mark) of
wheel with match mark (approx. 8mm diameter red paint mark)
of tire to assemble. If the match mark at wheel has
disappeared, align with air valve to assemble.


2. Wheel and Tire Assembly







3. Wheel Nut
Tighten wheel nuts in numerical order.
Wheel Nut Torque kgf
m (lb
ft/N
m)
12.0  1.0 (86.8  7.2 / 117.7  9.8)

3E-10 WHEELS AND TIRES

TROUBLESHOOTING
Typical examples of abnormal tire tread wear and major causes :

CAUTION:
Similar wear patterns can be caused by worn suspension parts, misalignment of wheels and tires, and
other suspension related problems.


Spotty wear - wear localized
on shoulder section. In
extreme cases, the tire
becomes polygonal in shape.
Tire or wheel out of
round or distorted.Hub or knuckle out
of round or distorted.Play in hub bearings
or ball joints.Rotating parts out of
balance.
Tread wear one-sided.
Rotating parts out of
balance.Tire or wheel out of
round.Hub or knuckle out
of round or distorted.
Localized tread wear.
Once spotty wear develops in
tread due to hard braking or
abrupt starting, localized wear
tends to be accelerated.

WHEELS AND TIRES 3E-11

Shoulder wear (generally
wear develops on outer
shoulder).
Camber or toe-in
incorrect.Shoulder wear
caused by repeated
hard-cornering.
Wear on shoulders at points
opposed to each other.
Tire or wheel out of
round or distorted.Play in bearings or
ball joint.
Premature wear on
shoulders.
Flexing of tire excessive due
to under-inflation.
One-sided feather edging.
Wear caused by
repeated hard-
cornering.Camber or toe-in
incorrect.

3E-12 WHEELS AND TIRES
MEMO

TRANSFER CONTROL SYSTEM 7D1-43
Even after the correction step 1-2(*), the 4WD indicator still blinks at 2Hz when shifting
from 2H to 4H.
Step Action Yes No
1 Check the air pressure and wear
of all the tires. Is any trouble
noticed? After adjusting the air pressure
and repairing the tire worn away,
try the correction step 1-2(*). Go to step 2.
2 Check the 4WD detection switch
on the transfer case, neutral
detection switch and each
harness. Is a trouble noticed? 4WD detection switch is open or
the harness failed.
The neutral detection switch is
closed or the harness GND is
shorted.
Replace or repair and then trace
this chart from the beginning. Go to step 3.
3 Is there continuity in the harness
between the transfer controller
and front axle actuator? Isn’t a
body short or disconnection
noticed? Go to step 4. Body short or disconnection of
the harness between the transfer
controller and front axle actuator.
After repairing, trace this chart
from the beginning.
4 Is a trouble noticed in the axle
detection harness between the
axle actuator and transfer
controller? Disconnected harness.
After repairing trace this chart
from the beginning. Malfunction of axle actuator.
Refer to the paragraph of the
axle disconnect.
After repairing, trace this chart
from the beginning.
*Before determining a trouble (Non-trouble mode)
Note:
The vehicle of manual hub and rigid hub don’t have axle actuator.
When the above-mentioned procedure is followed, check the harness between the axle dummy output terminal and
the axle switch input terminal of transfer controller instead of axle actuator.

7D1-46 TRANSFER CONTROL SYSTEM
Even after the correction step 2-1(*), the 4WD indicator still blinks at 2Hz when shifting
from 4H to 2H.
Step Action Yes No
1 Check all the tires for air
pressure and wear. Is any
trouble noticed? After adjusting the air pressure
and repairing the tire worn away,
try the correction step 2-1(*). Go to step 2.
2 Check the 4WD detection switch
on the transfer case and neutral
detection switch and each
harness. Is a trouble noticed? 4WD detection switch is closed
or the GND short of harness.
The neutral detection switch is
closed or the harness GND is
shorted.
Replace or repair and then trace
this chart from the beginning. Go to step 3.
3 Is there continuity in the harness
between the transfer controller
and axle actuator?
Isn’t short or disconnection
noticed?
Isn’t the connection mistaken? Go to step 4. Body short, disconnection or
incorrect connection of the
harness between the transfer
controller and actuator.
After repairing, trace this chart
from the beginning.
4 Is a trouble noticed in the axle
detection harness between the
axle actuator and transfer
controller? GND short of harness Malfunction of axle actuator.
Refer to the paragraph of axle
disconnect.
After repairing, trace this chart
from the beginning.
*Before determining a trouble (Non-trouble mode)

Note:
The vehicle of manual hub and rigid hub don’t have axle actuator.
When the above-mentioned procedure is followed, check the harness between the axle dummy output terminal and
the axle switch input terminal of transfer controller instead of axle actuator.

DIAGNOSIS (JR405E) 7A2-107
No. B10: Brake is Applied in R Range

Description:

Brake is applied suddenly in R range.

Diagnosis Hints:

Basically a trouble in the AT main unit. However, some trouble in the sensor system or output system may have
some influence on the trouble in the main unit and therefore these systems should be also checked to prevent
reproduce of the trouble.

Possible Cause:

Seized clutch (low clutch, high clutch, 2-4 brake).

Shortage or faulty quality of ATF.

Trouble in control valve body (faulty operation, sticking, clogged oil passage).

Disordered select cable (select indicator light indicates R but the hydraulic system is not in the R range).

Malfunction of parking mechanism.


No. B11: Insufficient Starting or Shaking in D Range

Description:

Insufficient starting or shaking in D range.

Possible Cause:

Slip of clutch (low clutch, low one-way clutch, reverse clutch, low & reverse brake).
If slip of clutch is caused, a DTC (gear ratio error) is stored.

Shortage or faulty quality of ATF.

Dropped line pressure.

Trouble in control valve body (faulty operation, sticking, clogged oil passage).


No. B12: Noise or Vibration is Generated at Starting

Description:

Noise or vibration is generated in the vicinity of AT at starting.

Diagnosis Hints:

Cause other than AT can be also considered. It is effective means to reproduce a running condition using a lift
up, chassis dynamo, etc. to investigate the origin (generating condition) of noise and vibration.
Caution:
Lifting up some unit to test it accompanies danger. Provide safety measures as far as possible and
carry out the test with sufficient care.

Possible Cause:
Following sources of noise or vibration other than the AT can be considered.

Noise from differential gears.

Noise from propeller shaft.

The bearing support in the middle of the propeller shaft has fatigued, and the bend angle of the propeller shaft
has changed, causing vibration at the time of start.

Unbalanced and poor uniformity of tires cause vibration.

7A2-130 DIAGNOSIS (JR405E)
No. F2: Engine Races Up During Acceleration (Slip)

Description:

The engine speed up when the accelerator pedal is stepped on for acceleration and the gear is shifted up or
down.

Only the engine speeds up but vehicle speed does not increase when the accelerator pedal is stepped on for
acceleration during the running.

Diagnosis Hints:

Basically same causes as "No. C1 - C8: Engine races up (slip) by shift up or shift down" are considered.
When the condition of No. C1-C8 grows worse, symptom of No. F2 results.




No. F3: Noise or Vibration During the Running in R, D, 3, 2 or L Range

Description:

Noise or vibration is generated in the vicinity of AT during the running.

Diagnosis Hints:

Cause other than AT can be also considered. It is effective means to reproduce a running condition using a lift
up, chassis dynamo, etc. to investigate the origin (generating condition) of noise and vibration.
Caution:
Lifting up some unit to test it accompanies danger. Provide safety measures as far as possible and
carry out the test with sufficient care.

Possible Cause:
Following sources of noise or vibration other than the AT can be considered.

Noise from differential gears.

Noise from propeller shaft.

The bearing support in the middle of the propeller shaft has fatigued, and the bend angle of the propeller shaft
has changed, causing vibration at the time of start.

Unbalanced and poor uniformity of tires cause vibration.




No. F4: Engine Brake Does Not Apply in L Range

Description:

The engine brake does not apply, allowing the vehicle to run freely when the accelerator pedal is released at low
speed in L range.

Possible Cause:

Slip of clutch (low & reverse brake)
If slip of clutch is caused, a DTC (gear ratio error) is stored.

Faulty input/output signal system.
Low & reverse brake duty solenoid

Faulty control valve (faulty operation, sticking).