
J
A
C
打印人:20122642 部门:客户服务部
Transmission System Service Manual N 125-NAM - PV - DP - G 9 - 18
10 / 72
(4)Abnormal sounds
Damage, wear, distortions, and the lost of the balance of drive shaft parts may cause abnormal sounds and vibration
when the vehicle is running, which even results in damage of relevant parts. If the vehicle sounds when starting or
accelerating, and shows the looseness, it is probably the loose of drive axle gear or that of drive shaft parts. The loose
probably locates in the universal joint cross shaft or the steel bowl and flange yoke, and spline shaft and spline sleeve of
the telescopic sleeve. The space between cross shaft diameter and bearing should not exceed 0.13 MM, backlash between
telescopic spline shaft and spline sleeve should not exceed 0.3 mm. Parts should be repaired or replaced if the limit is
over.
If chassis has a humming sound, and the higher the speed is, the louder the sound shows. This is typically caused by
the looseness between the universal joint and the bearings, or by the wear of the intermediate bearing of the transmission
shaft, or by the loose hanging bracket, or by the wrong position of the hanging bracket.
(5) Vibration
The noise increases with the speed, and it is accompanied by a shaking, this is generally caused by the imbalance of
drive shaft. This vibration in the cab can be felt obviously. The largest remaining imbalance of the drive shaft dynamic
balance is not bigger than 30/3200 ( g·cm/r/min). Invalidation of the drive shaft dynamic balance will result in the
damage of relevant parts, of which the most common is the clutch housing cracks.
Ways to Check:
Stuff up the front wheels with stow-wood, and jack up the drive axle from one side; start the engine, engage a high
speed to check the vibration of the drive shaft. If with the decrease of the speed the vibration is even significant, this
indicates that the drive is bent or flange is skew. It is often the axle tube that is bending, and this is mainly caused by
overload.
Replace drive shaft assembly, balance check should be carried out after the alignment, and the unbalanced volume
should be up to the required standard. The technical conditions of the universal joint and the transmission shaft also call
for detailed inspection. Undesirable installation may lead to looseness, vibration and damage of the cross shaft and roller,
which will also cause imbalance of the drive shaft.
5.2. Drive shaft maintenance