Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 595

3E–2

WHEEL AND TIRE SYSTEM

General Description

480R200012

Replacement wheels or tires must be equivalent to the
originals in load capacity, specified dimension and
mounting configuration.  Improper size or type may affect
bearing life, brake performance, speedometer/odometer
calibration, vehicle ground clearance and tire clearance
to the body and chassis.  All model are equipped with
metric sized tubeless steel belted radial tires.  Correct tire
pressures and driving habits have an important influence
on tire life.  Heavy cornering, excessively rapid
acceleration and unnecessary sharp braking increase
premature and uneven wear.

WHEEL AND TIRE SYSTEM

3E–3

Diagnosis

480RS001

Irregular and Premature Wear

Irregular and/or premature wear has many causes.
Some of them are incorrect inflation pressures, lack of tire
rotation, poor driving habits or improper wheel alignment.
Incorrect inflation is common cause of tire premature
wear.

NOTE: Due to their design, radial tires tend to wear faster
in the shoulder area, particularly on the front tires.  This
makes regular rotation especially necessary.  After
rotation, be sure to check wheel nut torque, and set tire
pressures. 

Tire Rotation

Tire rotation is recommended to equalize wear for longer
tire life.

480RS002

Legend

(1) Spare Tire

If the following conditions are noted, rotate the tires:

D

Front tire wear is different from rear.

D

Uneven wear exists across the tread of any tire.

D

Left and right front tire wear is unequal.

D

Left and right rear tire wear is unequal.

Check wheel alignment if the following conditions are
noted:

D

Left and right front tire wear is unequal.

D

Wear is uneven across the tread of any front tire.

D

Front tire treads have a scuffed appearance with
“feather” edges on one side of the tread ribs or blocks.

Tread Wear Indicators

480RS006

The original equipment tires have built-in tread wear
indicators(1) to show when tires need replacement.
These indicators may appear as wide bands.  When the
indicators appear in two or more grooves at three
locations, tire replacement is recommended.

3E–4

WHEEL AND TIRE SYSTEM

Inflation of Tires

710RS003

Tire pressure, in cold condition (after vehicle has set for
three hours or more, and driven less than one mile),
should be checked monthly or before any extended trip.
Tire pressure increases approximately 15% when the
tires become hot during driving.  Tire pressure
specification is shown on the label located on the left door
lock pillar.

NOTE: Check the tire pressure whenever irregular wear
is found.  Tire inflation greatly affects tire wear.  If the
alignment check does not reveal any alignment problems,
check the condition of the shock absorbers and wheel/tire
balance.

Diagnosis List

If the following conditions are noted, rotation is required.

1. Front tire wear is different from rear.
2. Uneven wear exists across the tread of any tire.
3. Left and right front tire wear is unequal.
4. Left and right rear tire wear is unequal. 

If the following conditions are noted, check the wheel
alignment.

1. Left and right front tire wear is unequal.
2. Uneven wear exists across the tread of any tire.
3. Front tire treads have scuffed appearance with

“feather” edges on one side of tread ribs or blocks.

4. There is cupping, flat spotting etc. 

Higher than recommended pressure can cause:

1. Hard ride.
2. Poor steering stability.
3. Rapid and uneven wear at center of the tread.

Lower than recommended pressure can cause:

1. Tire squeal on turns.
2. Hard steering.
3. Rapid and uneven wear on the edges of the tread.
4. Tire rim bruises and rupture.
5. Tire cord breakage.

6. High tire temperatures.
7. Reduced handling.
8. Reduced fuel economy.

Unequal pressure on same axle can cause:

1. Uneven braking.
2. Steering lead.
3. Reduced handling.
4. Swerve on acceleration.

Radial Tire Waddle

480RS007

Waddle is side-to-side movement at the front and/or rear
of the car. It can be caused by the steel belt not being
straight within the tire, or by excessive lateral runout of the
tire or wheel. It is most noticeable at low speed, about 8 to
48 km/h (5 to 30 mph). It may also cause rough ride at 80
to 113 km/h (50 to 70 mph).
The car can be road tested to see which end of the car has
the faulty tire.  If the tire causing the waddle is on the rear,
the rear end of the car will “waddle”. From the driver’s
seat, it feels as if someone is pushing on the side of the
car.
If the faulty tire is on the front, the waddle is more easily
seen. The front sheet metal appears to be moving back
and forth. It feels as if the driver’s seat is the pivot point in
the car.
Another more time-consuming method of determining the
faulty tire is substituting tire and wheel assemblies that
are known to be good. Follow these steps:

1. Drive the car to determine if the waddle is coming

from the front or rear.

2. Install tire and wheel assemblies known to be good

(from a similar car) in place of those on the end of the
car which is waddling. If the waddle cannot be
isolated to front or rear, start with the rear tires.

3. Road test again. If improvement is noted, install the

original tire and wheel assemblies one at a time until
the faulty tire is found. If no improvement is noted,
install tires known to be good in place of all four. Then,
install the originals one at a time until the faulty tire is
found.

WHEEL AND TIRE SYSTEM

3E–5

Radial Tire Lead/Pull

“Lead/Pull” is vehicle deviation from a straight path, on a
level road with no pressure on the steering wheel.
Lead is usually caused by:

1. Poorly manufactured radial tires.
2. Uneven brake adjustment.
3. Wheel alignment.

The way in which a tire is built can produce lead in a car.
An example of this is placement of the belt. Off-center
belts on radial tires can cause the tire to develop a side
force while rolling straight down the road and the tire will
tend to roll like a cone.
The  “Radial Tire Lead/Pull Correction” chart should be
used to make sure that front wheel alignment is not
mistaken for tire lead.
Rear tires will not cause lead/pull.