Page 494 - Foton Workshop Manual - Auman EST-M

DI - 440 Diagnosis - Mechanical fault diagnosis

Rear axle assembly fault

Overview

Rear axle assembly is mainly composed of final drive, differential, axle shaft and rear axle housing. The final
drive is a main component to reduce speed and increase torque in vehicle transmission system; the differential
is used to eliminate the rotational speed difference of driving wheels at two sides and of multi-axle driving
axle in case of vehicle steering; the axle shaft is also used to reliably transmit driving force; the rear axle
housing is installation base for main components of transmission system and running system.
Precautions
1. Please wear the necessary protective articles during repair to avoid the occurrence of accident.
2. Please check whether the vehicle lift is safe before repair.

3. Propose the use of genuine parts to ensure vehicle safety.
4. Do not reuse the bearing after it is dismantled.

5. Be sure to use the designated final drive gear. Any mixed use is forbidden.
6. Be sure to check the vent plug and remove dirt and dust on a regular basis.
7. Do not reuse all rubber elements (such O-ring, oil seal, washer, etc.) after they are dismantled.
8. Be sure to confirm that all components are clean and free of oil stain and iron dust before the final
drive is reassembled. Without special instruction, lubricate it with gear oil before operation.

Failure diagnosis

When the vehicle fails, first check visually for normal items. Items to be checked as follows:
● If there is obvious damage on the visible or easy to contact parts.
● If there is any additional installation after-sales which may cause system failure.

● If the parts are loose abnormally?
● Check the rear axle gear oil.
● Check the tooth surface engagement between driving and driven bevel gears.

● Check backlash of reducer gear pair.
● Check the backlash of differential gear pair.
When the vehicle fails, the corresponding phenomenon will appear. Common failures and trouble-shooting as
follows:

Failure phenomenon Possible reason Failure elimination

1. Gear oil (too little) Filling gear oil

Main reducer too hot 2. Drive and drive gears (too little gap) Adjustment

3. Differential mechanism bearing (too tight) Adjustment

DI-440