Chevrolet 1980 Light Duty Truck Service Manual page 333

1. Universal Joint Yoke
2. Pinion Bearing Oil
Seal and Retainer
3. Oil Seal
4. Oil Seal Gasket
5. Front Pinion Bearing
6. Drive Pinion
7. Rear Pinion Bearing
STA N D A R D DIFFERENTIAL
Noise
The most essential part of rear axle service, as with any
mechanical repair, is proper diagnosis of the problem, and,
in axle work one of the most difficult areas to diagnosis is
noise. Locating a broken axle shaft, or broken differential
gear, presents little or no problem, but, locating and
isolating axle noise can be an entirely different matter.
8 Ring Gear Thrust Pad
9. Ring Gear
10 Differential Spider
1 1. Differential Pinion
(Spider) Gear
12. Differential Side Gear
13. Differential Case-Left
Half
Fig. 4B -8~C hevrolet 1 2 -1 /4 " Ring Gear A xle-1 1 ,0 0 0 # C apacity
DIFFERENTIAL DIAGNOSIS
1 4. Axle Shaft
15. Differential Bearing
16 Differential Bearing
Adjusting Nut
17. Adjusting Nut Lock
18. Differential
C ase-Right Half
Degree of Noise
Any gear driven unit, and especially an automotive
drive axle where engine torque multiplication occurs at a
90° turn in the drive line, produces a certain amount of
noise. Therefore, an interpretation must be made for each
vehicle to determine whether the noise is normal or if a
problem actually exists. A normal amount of noise must be
expected and cannot be eliminated by conventional repairs
or adjustment. See figure 4B-9.
Acceptable noise can be defined as a slight noise heard
only at a certain speed or under unusual or remote
REAR AXLE 4B-7
LIG H T T R U CK SER V ICE M AN U AL