Isuzu 2000 Trooper Workshop Manual page 280

WHEEL AND TIRE SYSTEM
3E–4
Inflation of Tires
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.
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
710RS003
Tire pressure
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.
480RS007