768C TRACTOR & 769C TRUCK POWER TRAIN Caterpillar

(1) Torque for 12 long studs marked with an "X" ... 350 ± 40 N·m (260 ± 30 lb ft)

(2) Located bleed screws in top set of ports when assembled on right or left hand side of machine.

(3) Put 2P-2506 Thread Lubricant on face of washers and threads of nuts. Tighten the 18 nuts to a torque of ... 715 ± 25 N·m (525 ± 20 lb ft)

(4) Torque for six short studs ... 350 ± 40 N·m (260 ± 30 lb ft)

(5) Put lubricant on seal.

(6) Rim mounting surfaces must be clean and free of oil and grease before wheel assembly is installed.

(7) 4D-5642 Shim thickness (new) ... 2.90 ± 0.08 mm (.114 ± .003 in)

(8) Torque for eight bolts ... 250 ± 14 N·m (185 ± 10 lb ft)

(9) Put 2P-2506 Thread Lubricant on faces of washers and threads of nuts before assembly. Torque for nuts ... 1205 ± 55 N·m (890 ± 40 lb ft)

NOTE: If 2P-2506 Thread Lubricant is not available, do not use any other type of lubricant. Clean studs (1) and (4), bolts (10), nuts (3) and (9) and washers with a solvent. Make sure each item is dry, and then tighten the nuts to ... 1825 ± 55 N·m (1340 ± 40 lb ft)

Adjustment Of The Rear Wheel Bearings

Typical Example

Typical Example

Typical Example

Typical Example

Typical Example

NOTE: Before adjustment of the rear wheel bearings can be made, the parking brake and the service brake must be released. To release the service brake, see the topic TOWING in the Systems Operation, Testing and Adjusting (Air System and Brakes). To release the parking brake, remove the bleed valve from opening (A), marked "P" and connect a manual or electric hydraulic pump to the opening. Operate the pump until the brake is released.

NOTE: Hand tap or wire brush the threaded holes to remove thread lock or patch material prior to doing Step 1.

NOTE: If the wheel assembly has 5P-9118 Self Locking Bolts do not use them for the bearing preload. Use OS-1625 Bolts to set the bearing preload. Also, use the 0S-1625 Bolts for final assembly.

1. Put the retainer, Duo-cone seal, wheel and bearings, and final drive hub in position on the axle housing.

2. Install retainer (1) without shims (7). Use three bolts as near evenly spaced as possible, to hold the retainer.

3. To seat the bearings, turn the wheel several times while tightening the bolts.

4. As the wheel IS TURNED, tighten the bolts to ... 70 N·m (50 lb ft)

5. Use depth micrometer (2) to measure through the threaded holes in the retainer and find the average depth.

6. Use outside micrometer (3) to measure the thickness of the retainer at the threaded holes and find the average thickness.

7. Find the difference between the two average measurements. This difference is the gap between end of the axle housing and the retainer.

8. Remove the retainer. Install shims (7) equal to the average gap found in Step 7 plus ... 0.10 mm (.004 in)

NOTE: Apply 9S-3263 Thread Lock to six bolts before assembly.

9. Install retainer (1) and shims (7). Tighten the bolts that hold the retainer to the axle housing to a torque of ... 250 ± 14 N·m (185 ± 10 lb ft)

NOTE: If micrometers are not available, use the procedure below:

NOTE: Hand tap or wire brush the threaded holes to remove thread lock or patch material prior to doing Step 1.

NOTE: If the wheel assembly has 5P-9118 Self Locking Bolts do not use them for the bearing preload. Use 0S-1625 Bolts to set the bearing preload. Also, use the 0S-1625 Bolts for final assembly.

1. Put the retainer, Duo-Cone seal, wheel and bearings, and final drive hub in position on the axle housing.

2. Install retainer (1) without shims (7). Use three bolts as near evenly spaced as possible, to hold the retainer.

3. To seat the bearings, turn the wheel several times while tightening the bolts.

4. As the wheel IS TURNED, tightened the bolts to ... 70 N·m (50 lb ft)

5. Install two 1/2 in - 13 screws (4) with locknuts into the threaded holes in retainer (1). Tighten screws (4) by hand until they are against the end of the axle housing. Tighten the locknuts against the retainer.

6. Remove retainer (1). With a straight edge (5) across the screws, measure distance (A) from the inner face of retainer (1) to the ends of screws (4) with a feeler gauge.

7. Install enough shims (7) between the axle housing and retainer so they are 0.10 mm (.004 in) thicker than distance (A) measured.

NOTE: Apply 9S-3263 Thread Lock to six bolts before assembly.

8. Install retainer (1) and shims (7). Tighten the bolts, that hold the retainer to the axle housing, while turning the wheel to a torque of ... 250 ± 14 N·m (185 ± 10 lb ft)