IT28G Integrated Toolcarrier and 924G, 924GZ and 928G Wheel Loaders Differential and Final Drive Caterpillar

Show/hide table

Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To prevent possible injury, perform the procedure that follows before testing and adjusting the power train.

Show/hide table

Personal injury can result from hydraulic oil pressure and hot oil. Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system. Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.

Problem List

Note: Many of the following problems can create diagnostic codes or event codes in ET. These codes can help find the root cause of the problem. ET should be used to retrieve the logged codes and active codes.

1. There is constant noise in the differential.

2. There is noise at different intervals.

3. There is noise when the machine turns.

4. There is leakage of lubricant.

5. The drive wheels do not turn, but the universal joint turns.

Probable Causes

Problem 1

There is constant noise in the differential.

Probable Causes

1. The lubricant is above the proper level or below the proper level.

2. The lubricant is the wrong type.

3. The wheel bearings are out of adjustment or the wheel bearings are worn.

4. The ring gear and the pinion do not have the correct tooth contact.

5. The ring gear and the pinion are damaged or worn.

6. There is too much pinion to gear backlash or there is too little pinion to gear backlash.

7. The pinion bearings are loose or worn.

8. The side bearings are loose or worn.

Problem 2

There is noise at different intervals.

Probable Causes

1. The ring gear does not run even because the bolts on the ring gear are not tight.

2. The ring gear does not run even because the ring gear is warped.

3. The differential bearings are loose or broken.

Problem 3

There is noise when the machine turns.

Probable Causes

1. The differential pinion gears are too tight on the retainer pins or the pinion shaft.

2. Side gears are too tight on the pinion shaft.

3. The differential pinion or side gears are worn.

4. Thrust washers are worn or damaged.

5. There is too much backlash between the side and pinion gears.

Problem 4

There is leakage of lubricant.

Probable Causes

1. Lubricant is leaking out of the axle shafts because the lubricant is above the proper level.

2. Lubricant is leaking out of the axle shafts because of the wrong type of lubricant.

3. Lubricant is leaking out of the axle shafts because the axle housing breather is restricted.

4. Lubricant is leaking out of the axle shafts because the oil seal for the axle shaft is suspect.

5. Lubricant is lost at the pinion shaft because the lubricant is above the proper level.

6. Lubricant is lost at the pinion shaft because of the wrong type of lubricant.

7. Lubricant is lost at the pinion shaft because the axle housing breather is restricted.

8. Lubricant is lost at the pinion shaft because the oil seal for the pinion is suspect.

9. Lubricant is lost at the pinion shaft because the universal joint flange is loose on the pinion shaft.

Problem 5

The drive wheels do not turn, but the universal joint turns.

Probable Causes

1. The axle shaft is broken.

2. Ring gear teeth are damaged.

3. The side gear is broken or the differential is broken.

4. The differential pinion shaft is broken or the retainer pin is broken.