SsangYong Korando III (2010 year). Manual — part 249

14-6

During driving, the rotating tire repeats deformation and restoring movement in is tread. This happens

when the tire pressure is low in high speed driving.

However, when the wheel rotating speed is fast, the tire is deformed even before it is restored to its

original shape and the trembling wave appears on the tread portion. If this symptom lasts for an

extended period of time, the tire can be blown out in a short period of time.

If the standing wave symptom occurs on the tire, rubber on the tread comes off and eventually the tire

can be blown out which is very dangerous. When driving at high speed, the inflation pressure should be

increased to decrease heat generation due to extension and contraction motion, to decrease

hydroplaning and to prevent standing wave.

To prevent this symptom, it is recommended to increase the tire pressure 10 ~ 30 % higher than the

specified pressure value in high speed driving.

Specified tire inflation pressure

32psi

2. ABNORMAL TIRE SYMPTOM

1) Standing Wave

14-7

4170-00

When the vehicle is driven on a road surface covered with water at high speed, tires do not contact with

the road surface but rotate floating on a thin film of water.

It causes brake failure, lower traction force and losing the steering performance.

To prevent this, increase the tire inflation pressure, use tires with leaf shape tread which is not worn.

However, it is a best measure to drive slowly.

2) Hydro Planing

14-8

If weight is not equally distributed around the wheel, unbalance centrifugal force by the wheel rotation

produces vibration. As the centrifugal force is produced proportional to the square of the rotating speed,

the wheel weight should be balanced even at high speed. There are two types of the tire and wheel

balancing: static and dynamic. Abnormal vibration may also occur due to unbalanced rigidity or size of

tires.

1) Static Balance

When the free rotation of the wheel is

allowed, the heavier part is stopped on the

bottom if the wheel weight is unbalanced and

this is called "Static Unbalance". Also, the

state at which tire's stop position is not same

is called "Static Balance" when the wheel is

rotated again. If the part A is heavier as

shown in the figure 1, add the balance weight

of a weight corresponding to unbalanced

weight from B to A to maintain the static

balance. If the static balance is not

maintained, tramping, up and down vibration

of the wheels, occurs.

2) Dynamic Balance

The static unbalance of the wheel creates

the vibration in the vertical direction, but the

dynamic unbalance creates the vibration in

the lateral direction. As shown in the figure

2 (a), if two parts, (2) and (3), are heavier

when the wheels are under the static

balance condition, dynamic unbalance is

created, resulting in shimmy, left and right

vibration of the wheels, and the torque Fxa

is applied in the axial direction. To correct

the dynamic unbalance, add the balance

weight of a same weight for two points of

the circumference of the rim, A and B, as

shown in the figure 2 (b), and apply the

torque in the opposite direction to the

torque Fxa to offset in order to ensure

smooth rotation of the wheel.

Center

A

B

a

a

Fxa

Fxa

F

F

A

B

(a)

(b)

[Figure 1]

[Figure 2]

3. WHEEL BALANCE

15-3

4012-00

1. SPECIFICATION

Unit

Construction

Front sub
frame

Rear sub
frame (4WD)

Rear sub
frame (2WD)

Body mounting:

4-points bush

Transaxle mounting:

2-points bush

Weight: 22.37 kg

1.

2.

3.

Body mounting:

4-points bush

Axle mounting:

4-points bush

Weight: 16.61 kg

1.

2.

3.

Body mounting:

40 points direct mounting

Spring link:

Direct mounting without

bracket on rear cross

member

Weight: 12.74 kg

1.

2.

3.