SsangYong Musso. Manual - part 223

2B-2  WHEEL ALIGNMENT

DIAGNOSIS

TIRE DIAGNOSIS

Irregular and Premature Wear

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

Rotate the tires if :

!

The front tire wear is different from the rear.

!

The left and right front tire wear is unequal.

!

The left and right rear tire wear is unequal, Check
wheel alignment if :

!

The left and right front tire wear is unequal.

!

The wear is uneven across the tread of either front
tire.

!

The front tire treads are scuffed with “feather” edges
on the side of the tread ribs or blocks.

Tread Wear Indicators

The original equipment tires have built-in tread wear
indicators to show when the tires need replacement.
These indicators appear as bands when the tire tread
depth becomes shallow. Tire replacement is
recommended when the indicators appear in three or
more grooves at six locations.

Radial Tire Waddle

Waddle is side-to-side movement at the front or rear of
the vehicle. It is caused by the steel belt not being straight
within the tire, or by excessive lateral runout of the tire
or wheel.

The vehicle must be road tested to determine which end
of the vehicle has the faulty tire. The rear end of the
vehicle will shake from side to side or “waddle” if the
waddle tire is on the rear of the vehicle. From the driver’s
seat, it feels as though someone is pushing on the side
of the vehicle. If the faulty tire is on the front of the vehicle,
the waddle is more visual. The front sheet meld appears
to be moving back and forth, and the drivers seat feels
like the pivot point in the vehicle.

Waddle can be diagnosed using the method of
substituting known good tire and wheel assemblies on
the problem vehicle

1. Road test the vehicle to determine if the waddle is

coming from the front or the rear of the vehicle.

2. Install good tires and wheels from a similar vehicle in

place of those on the offending end of the problem
vehicle. If the source of the waddle is not obvious,
change the rear tires.

WHEEL ALIGNMENT  2B-3

3. Road test the vehicle. If there is improvement, install

the original tires to find the offending tire. If there is
no a straight improvement, install good tires in place
of all four offending tires.

4. Install original tires one at a time to find the offending

tire.

RADIAL TIRE LEAD/PULL

Lead/pull is the deviation of the vehicle from a straight
path on a level road with no pressure on the steering
wheel. Lead is usually caused by:

!

Incorrect alignment.

!

Uneven brake adjustment.

!

Tire construction.

The way in which a tire is built can produce lead/pull in
the vehicle.011-center belts on radial tires can cause
the tire to develop a side force while the vehicle rolls
straight down the road. If one side of the tire has even a
little larger diameter than the diameter of the other side,
the tire will tend to roll to one side. Unequal diameters
will cause the tire to develop a side force which can
produce vehicle lead/pull.

The radial lead/pull diagnosis chart should be used to
determine whether the problem originates from an
alignment problem or from the tires. Part of the lead
diagnosis procedure calls for tire rotation that is different
from the proper tire rotation pattern. If a medium- to high-
mileage tire is moved to the other side of the vehicle, be
sure to check for ride roughness. Rear tires will not cause
lead/pull.

2B-4  WHEEL ALIGNMENT

1. Perform wheel alignment preliminary inspection.
2. Check the brakes for dragging.
3. Road test the vehicle.
Does the vehicle lead/pull?

1. Cross switch the front tire and wheel assemblies.
2. Road test the vehicle.
Does the vehicle lead/pull?

1. Check the front wheel alignment.
Is the alignment within specifications?

1. Compare the front camber and front caster to
specifications.
Are they within specifications?

1. Check the vehicle frame.
Is the frame bent?

1. Straighten the frame.
Is the repair complete?

1. The probable cause is the tires.
2. Switch the left front tire and wheel assembly with
the left rear tire and wheel assembly.
3. Road test the vehicle.
Does the vehicle still lead/pull?

1. Switch the left front tire and wheel assembly with
the left rear tire and wheel assembly and replace the
left front tire.
Does the repair complete?

1. Switch the right front tire and wheel assembly with
the right rear tire and wheel assembly.
2. Road test the vehicle.
Does the vehicle still lead/pull?

1. Switch the right front tire and wheel assembly with
the right rear tire and wheel assembly and replace
the right front tire.
Is the repair complete?

Action

Radial Tire Lead/Pull Diagnosis Chart

Step

1

Values(s)

-

Yes

Go to Step 2

Go to Step 3

Go to Step 4

Go to Step 7

Go to Step 6

Go to Step 3

Go to Step 9

System OK

Go to Step 1

System OK

No

System OK

System OK

Adjust

alignment

Go to Step 5

Go to Step 1

-

Go to Step 8

Go to Step 1

Go to Step 10

Go to Step 1

2

3

4

5

6

7

8

9

10

-

-

-

-

-

-

-

-

-

WHEEL ALIGNMENT  2B-5

VIBRATION DIAGNOSIS

Wheel imbalance causes most highway speed vibration
problems. A vibration can remain after dynamic
balancing because:

!

A tire is out of round.

!

A rim is out of round.

!

A tire stiffness variation exists.

Measuring tire and wheel free runout will uncover only
part of the problem, All three causes, known as loaded
radial runout, must be checked using method of
substituting known good tire and wheel assemblies on
the problem vehicle.

Preliminary Checks

Prior to performing any work, always road test the car
and perform a careful visual inspection for:

!

Obvious tire and wheel runout.

!

Obvious drive axle runout.

!

Improper tire inflation.

!

Incorrect trim height.

!

Bent or damaged wheels.

!

Debris build-up on the tire or the wheel.

!

Irregular or excessive tire wear.

!

Improper tire bead seating on the rim,

!

Imperfections in the tires, including: tread
deformations, separations, or bulges from impact
damage. Slight sidewall indentations are normal and
will not affect ride quality.

Tire Balancing

Balance is the easiest procedure to perform and should

be done first if the vibration occurs at high speeds. Do
an off-vehicle, two-plane dynamic balance first to correct
any imbalance in the tire and wheel assembly.

An on-vehicle finish balance will correct any brake drum,
rotor, or wheel cover imbalance, If balancing does not
correct the high-speed vibration, or if the vibration occurs
at low speeds, runout is the probable cause.