793C Off-Highway Truck/Tractor Power Train Caterpillar

Transmission, Rear Axle Housing, and Wheel Group - Remove

Usage:

793C 4AR

Removal Procedure

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Table 1
Required Tools
Tool	Part Number	Part Description	Qty
A⁽¹⁾	9U-7536	Lift Stand	2
	447-0910	Electric Hydraulic Pump Gp (115V)	1
	447-0911	Electric Hydraulic Pump Gp (230V)	1
A1	OR
	504-9826	Lift Gp (60Hz)⁽²⁾	2
	504-9827	Lift Gp (50Hz)⁽³⁾	2
B	175-5507	Nitrogen Charging Group	1
C	FT-1845	Brake System Pump	1
C	030-8194	Flared Connector	1

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⁽¹⁾	Use Tooling (A) or (A1) based on requirements.
⁽²⁾	Operating-Voltage (380-500V)
⁽³⁾	Operating-Voltage (180-300V)

Start By:

Remove the truck body.

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The space between the body and the frame becomes a zero clearance area when the body is lowered. Failure to install the retaining cable can result in injury or death to personnel working in this area.

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At operating temperature, the oil in the power train is hot and under pressure. Hot oil can cause burns. Remove the breather filter cap when the engine is stopped and the breather cap is cool enough to touch by hand.

Slowly loosen the breather filter cap in order to release any pressure in the oil tank. Be careful of hot hydraulic oil when any lines are disconnected from the components of the power train.

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NOTICE

Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, PERJ1017, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat^® products. Dispose of all fluids according to local regulations and mandates.

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NOTICE

Keep all parts clean from contaminants. Contaminants may cause rapid wear and shortened component life.

Position the truck on a level surface.
Drain the oil from the hoist and brake tank into a suitable container. The capacity of the hoist and brake tank is approximately 1137 L (300.4 US gal).
Drain the oil out of the transmission and torque converter system. The capacity of the transmission and torque converter system is approximately 227 L (59.9 US gal).
Drain the oil from the differential housing into a suitable container. The capacity of the differential housing is approximately 663 L (174.9 US gal).
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Illustration 1 g00517009

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Illustration 2 g00529796

Note: This procedure is for the removal of the differential, the rear wheel assembly, the transmission, and the rear tires as an assembly.
Remove hoses (29) and (34).
Disconnect hoses (19) and (20).
Remove bolt (16), the washer, split clamp (17), and clamp (18).
Remove bolt (12), the two washers, nut (13), clip (14), and clip (15).
Disconnect hose (23).
Remove bolt (1), the washer, clip (2), and clip (3).
Remove bolt (4), the washer, clip (5), and clip (6).
Remove bolt (7), the washer, and clip (8).
Remove bolt (9), the washer, clip (10), and clip (11).
Remove four bolts (24), eight washers, and two clips (26). Reposition lubrication injector banks (25) between the rear lamps. Temporarily secure the lubrication injector banks.
Remove two nuts (31). Disconnect the harness from bypass switch (32) of VIMS for the differential oil filter.
Disconnect oil level switch (33) of VIMS for the right differential.
Disconnect oil level switch (30) of VIMS for the left differential.
Remove bolt (27), the washer, and clip (28).
Remove two bolts (21), two washers, and two clips (22).
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Illustration 3 g00517013
Remove two bolts (35), two washers, and two clips (36).
Disconnect right wheel speed sensor (37) of the TCS
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Illustration 4 g00517014
Remove two bolts (38), two washers, and two clips (39).
Disconnect left wheel speed sensor (40) of the TCS.
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Illustration 5 g00517015
Remove four bolts (41), four washers, and four clips (42).
Disconnect differential oil temperature sensor (51) of VIMS.
Disconnect differential oil pressure sensor (43) of VIMS.
Remove two bolts (44), two washers, and two split clamps (45).
Remove bolt (46), the washer, and clip (47).
Remove bolt (48), the washer, and split clamp (49).
Disconnect hose (50).
Remove bolt (52), the washer, and clip (53).
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Illustration 6 g00517016
Remove bolt (58), the washer, and split clamp (59). Reposition the hose for the removal of the differential housing and the rear frame support.
Disconnect hose (55).
Remove bolt (60), the washer, and clip (61).
Disconnect left rear brake oil temperature sensor (54) of VIMS.
Remove four bolts (56), four washers, and split flange (57).
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Illustration 7 g00517038
Remove four bolts (64), four washers, and split flange (65). Disconnect hose (66). Reposition the hose for the removal of the differential housing and the rear frame support.
Remove four bolts (62), four washers, and four clips (63).
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Illustration 8 g00517040

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Illustration 9 g00517042

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Illustration 10 g00517044
Disconnect hoses (67) and (68).
Disconnect transmission oil temperature sensor (71).
Remove four bolts (72), four washers, two clips (73), and guard (74).
Disconnect the electrical harness connection to solenoid valve (75). Repeat this procedure for two remaining solenoid valves (76) and (77).
Disconnect hoses (78), (79), (80), and (81).
Disconnect bolt (82), the washer, and clip (83).
Disconnect electrical harness connection (84).
Remove six bolts (69), six washers, and six clips (70).
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Illustration 11 g00517045
Remove nine bolts (85), nine washers, and rear drive shaft guard (89).
Disconnect right rear brake oil temperature sensor (94).
Disconnect transmission output speed sensor (86) of the EPTC II.
Remove four bolts (87), four washers, and split flange (88).
Remove bolt (95), the washer, and two clips (96).
Remove two bolts (90), two washers, clip (91), plate (92), and two spacers (93). Reposition the hoses for the removal of the differential housing and the rear frame support.
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Illustration 12 g00517047
Remove four bolts (97). Disconnect drive shaft (98).
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Illustration 13 g00517048
Remove four bolts (99), four washers, and split flange (100). Disconnect the hose. Reposition the hose for the removal of the differential housing and the rear frame support.
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Illustration 14 g00517049
Remove four bolts (105), four washers, and split flange (106). Disconnect hose (101).
Remove four bolts (102), four washers, and split flange (103). Disconnect hose (104).
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Illustration 15 g00517050
Remove bolt (108), the washer, and bracket (109). Remove the two hoses and the bracket as an assembly.
Disconnect hose (107).
Remove four bolts (110), four washers, and split flange (111). Disconnect hose (112). Reposition the hose for the removal of the differential housing and the rear frame support.
Repeat Step 59 for hoses (113) and (114).
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Illustration 16 g00517051

For Tooling (A)
Position Tooling (A) under the hoist cylinder brackets. Support the rear of the truck. Use Tooling (A) to lift the frame. Provide 254 mm (10.0 inch) of clearance between the differential housing and the frame.
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Illustration 17 g06406464

For Tooling (A1)
Position Tooling (A1) under the hoist cylinder brackets. Support the rear of the truck. Use Tooling (A1) to lift the frame. Provide 254 mm (10.0 inch) of clearance between the differential housing and the frame. Refer to Tool Operating Manual, NEHS1328, "Lift Group (Stand - 60 Ton)" for more information on Tooling (A1).
Use Tooling (B) to remove the nitrogen charge from the rear suspension cylinders. Remove rear suspension cylinder (115) (not shown).
Position a suitable lift truck behind the differential housing. Use chains to secure the differential housing to the lift truck.
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Illustration 18 g00517052

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Illustration 19 g00517054
Use Tooling (C) to release the rear parking brakes. Apply approximately 3445 kPa (499.7 psi).
Note: Do not exceed a pressure of 4150 kPa (601.9 psi). The brakes may be damaged if the pressure is exceeded.
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Illustration 20 g00517055
Remove hose (116).
Support the weight of the lateral control rod. Remove bolt (117)(not shown), the washer, and retainer (118)(not shown). The lateral control rod weighs approximately 150 kg (330.7 lb). Remove pin (119)(not shown). Lower the upper end of lateral control rod (120).
Use Tooling (A) or (A1) to raise the rear end of the truck frame. Raise the truck frame until the lateral control rod clears the connection with the frame.
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Illustration 21 g00517056
Remove 12 bolts (121) and 12 washers.
Lower the front end of rear frame support (122) by approximately 75 mm (2.9 inch). Separate the rear frame bearing from the frame.
Move the transmission, the rear axle housing, and the wheel group assembly toward the rear of the truck. Use the lift truck to move the group. Use the hoist to support the rear frame bearing. The transmission, the rear axle housing, and the wheel group assembly weigh approximately 42000 kg (92594.04 lb).
When the hoist is close to the cross member of the rear frame, place a jack under the rear frame bearing. Remove the chains from the rear frame bearing. Move the hoist to the rear of the cross member. Support the rear frame support. Remove the jack from the rear frame bearing. Continue to remove the transmission, the rear axle housing, and the wheel group assembly under the machine.
After the transmission, the rear axle housing, and the wheel group assembly are removed from the truck, place a jack under the rear frame bearing. Place wheel chocks at the tires to prevent movement.