The differential for the front axle has an arrangement which allows the differential to be locked and the mechanism enables the axle shafts of the universal joints to be locked together. Both wheels can then rotate at the same speed and torque regardless of different ground resistance between the wheels.
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| Illustration 1 | g00726964 |
Differential Lock Control Switch | |
The differential lock is controlled by a two-position spring return switch that is located on the instrument panel of the machine. The differential lock is engaged by oil pressure when the switch is held down. The differential lock is disengaged by spring force when the switch is released.
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| Illustration 2 | g00726965 |
Solenoid Control Valve for Differential Lock (Earlier Machines) | |
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| Illustration 3 | g00726987 |
Solenoid Control Valve for Differential Lock (Later Machines) | |
The switch for the differential lock control operates a solenoid control valve. Supply to the solenoid control valve is from a pressure reducing valve that is located in the end section of the bank valve which controls the implement hydraulic system.
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| Illustration 4 | g00726966 |
Differential Lock (1) Change selector (2) Axle shaft (universal joint) (3) Differential cover (4) Axle shaft (universal joint) (5) Spring (6) Piston (7) Lever | |
A dog clutch is formed via change selector (1) and differential cover (3). The change selector has six dog teeth that are formed onto the flange that is opposite the differential. The change selector is installed via splines onto axle shaft (2). The differential cover has six mating teeth that can engage with the six dog teeth of the change selector. The change selector can slide axially on the axle shaft and this allows engagement and disengagement of the dog clutch.
In normal operation, the differential is unlocked and the axle shafts (2) and (4) are free to rotate at different speeds. The wheel speed is governed by the resistance at the wheel.
In this condition, change selector (1) is offset to the left and clear of differential cover (3) by the force of spring (5) .
When the switch for the differential lock control is operated, the control solenoid valve is energized open and piston (6) is offset against the force of spring (5) by oil pressure. The piston moves lever (7) and change selector (1) to the right into contact with differential cover (3) and the mating teeth in the differential cover engage with the dog teeth of the change selector when the components are rotated.