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Massey Ferguson 5455, 5460, 5465 - Rear axle differential lock

MF 5400 Series Tractors Service and Repair

The left-hand flange contains the differential lock mechanism. The system consists of a piston and a mobile dog clutch splined with the left-hand trumpet housing input sun gear. The mobile dog clutch is moved by the piston which is supplied by the 17 bar hydraulic system via a solenoid valve fitted on the right-hand cover plate.

The piston moves and pushes against the mobile dog clutch, compressing the spring. The teeth of the mobile dog clutch engage with a fixed dog clutch that is attached to the differential unit. In this position, the right and left-hand trumpet housing input sun gears turn at the same speed. When the pressure is released, the mobile dog clutch is driven back by the spring.

Parts list - (1) "O" ring (2) Stud (3) "O" ring (4) Circlip (5) Piston (6) Spring (7) Mobile dog clutch (8) "O" ring (9) Left-hand flange (10) Differential lock hydraulic assembly (11) Friction washer (12) Finger (13) Deflector (14) Bearing cup (15) Screw (16) Fixed dog clutch (17) Bearing cone (18) Washer (19) Sun gear (20) Planet gears (21) Washer (22) Spider (23) Ring gear (24) Rivets (25) Right-hand flange (26) Screw (27) Bearing cup (28) Bearing cone (29) Unit (30) Bearing cone (31) Bearing cone (32) Screw (33) Bearing cup (34) Pinion (35) Thrust plate (36) Shim(s) (37) Bearing cup (38) Shim(s) (39) Union (40) Differential lock supply pipe (41) Lubrication plug (42) Clip nut (differential support) (44) Washer (45) Locating ring (differential support) (46) Stud (47) Pipe (48) Union (49) Shim(s) (50) Shim(s) (51) Nut (securing the lubrication pipe) (52) Lubricating union (53) Spool valve tank return pipe (54) Clip nut (55) Clip nut (differential support) (56) Screw

MF 5435, 5445, 5455, 5460, 5465, 5470, 5475 - Removing the left-hand flange and differential lock assembly

It is possible to carry out maintenance on the differential lock hydraulic assembly (10) by removing only the left-hand trumpet housing.

Remove the left-hand trumpet housing. Disconnect the supply pipe (2), unscrew the union (39) and take out the pipe (40). If access to the union (39) is difficult on tractors fitted with 4-speed economy PTO, remove the control (1). Remove the brake piston. Purpose of the studs (2) and (46). Stud (2): this helps to attach the left-hand flange (9). it holds the lubrication pipe (47) for the pinion (34).

To reach the nut (3), remove the auxiliary spool valve support and work through the resulting opening. If this operation has to be carried out on a tractor fitted with 4-speed economy PTO, it is necessary to also remove the hitch hook support and the PTO top cover plate located at the rear of the tractor, the double gear and the control fork. Stud (46): this attaches the right-hand flange (25).

It supports the return pipe (53) of the hydraulic spool valves. The two studs (2) and (46) are fitted in the housing with a locking product (Loctite 242 or equivalent). The nuts on either side are tightened like the other screws holding the flanges, to a torque of 85-100 Nm. Remove the flange (9), the locating ring (45), and if necessary, the friction washer (11), the mobile dog clutch (7) and the spring (6).

Massey Ferguson 5435, 5445, 5455, 5460, 5465, 5470, 5475 - Disassembling and reassembling the differential lock assembly

Differential lock disassembly

Take out cup (14), deflector (13) and shim (49) (if fitted). Mark the deflector fitting direction and the location of the shim (49). Remove the circlip (4). Take out the piston (5) using a jet of compressed air. Remove the "O" rings (3) (8) (1). Unscrew the finger (12) (if necessary).

Differential lock reassembly

Check the components and replace those that are defective. Clean finger (12), smear it with Loctite 542, then Install it and tighten it on flange (9). Smear the "O" rings (3) (8) with miscible grease ("Amber Technical" or equivalent), and fit them correctly in the bottom of their respective grooves. Using a plastic hammer, insert the piston (5) into the flange (9) while respecting the location of the finger (12). Install the circlip (4), the shim (49) (if necessary), and the deflector (13), respecting its fitting direction, and the cup (14). The shim (49) (if used) must be fitted between the flange (9) and the deflector (13).

MF 5435, 5445, 5455, 5460, 5465, 5470, 5475 - Reinstall the left-hand flange and the differential lock assembly

Install the "O" ring (1). Assemble the washer (11), the mobile dog clutch (7) and the spring (6). Reinstall the assembly in the left-hand flange (9). Flange (9) fitting method.

Screw two guide studs "G" (L = 60 mm approx.) onto the centre housing. Check for the presence of the ring (45). Position the flange assembly (9) turning it so that the oil passage is facing downwards. Install the washer (44). Tighten alternately and uniformly the screw (56) and nut (42) to a torque of 85-100 Nm. Install the pipe (40) and the union (39).

Sealing test

If maintenance has been carried out on the piston (5), seals (3) (8) or flange (9), it is necessary to check the sealing of the assembly. Install a pressure gauge that has been previously tested for tightness to the supply union (39). Supply the system with compressed air at approximately 5 bar to correctly place the piston and the "O" rings in the left-hand flange (9). Reduce the pressure to 0.3 bar and carry out the sealing test. Close the valve.

For approximately one minute, no drop in pressure should be observed on the pressure gauge. Disconnect the pressure gauge and connect the supply pipe (2). If removed, reconnect the 4-speed economy PTO control and set the control. Reinstall the brake piston and the left-hand trumpet housing. Start the engine. Check the sealing of the supply pipe (2) and the correct operation of the differential lock.

MF TRACTORS TROUBLESHOOTING
1652	1749	2620	2725	2805
3050	3120	3640	3709	4245
4455	5320	5455	5613	6150
6280	6480	6615	7618	7720