Spicer Single Drive Axles Service Manual: Single Reduction & Single Reduction with Differential Lock - Manual (Page 58)

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Towing
Proper Vehicle Towing
Towing of Axles Equipped with Wheel Dif-
ferential Lock
1. Engage the wheel differential lock until the indicator
light is on (move vehicle to verify engagement).
2. Shift transmission into neutral.
3. With vehicle stationary, release the air pressure on
the wheel differential. lock shift system and apply the
parking brake.
4. Disconnect the air supply and fitting at the shift cyl-
inder.
5. Install the shipping cap screw or 128274 (M12 X 1.5
screw) or 128642 (.250 X 18 NPSM screw). Manu-
ally engage the wheel diff. lock until the indicator
light is on and the main differential lock is com-
pletely engaged.
6. Remove the axle shafts.
Note: Axle shafts are location specific. Remember the double-
splined or extended splined axle shafts are located on
the “shift cylinder” side of the axle.
7. Install temporary cover on hub to prevent contami-
nation entering and also to prevent the loss of lubri-
cant.
Description
The Spicer Wheel Differential Lock is an optional feature for
Spicer Axles. In operation, it positively locks the wheel dif-
ferential to provide improved traction under adverse road
conditions.
The differential lock is driver-controlled through an electric
switch or air valve mounted in the cab. The locking mecha-
nism is air-operated to engage a mechanical clutch and lock
the wheel differential. It is spring-operated to disengage the
lock and permit the wheel differential to function normally.
The Wheel Differential Lock consists of three major assem-
blies .
• A shift cylinder assembly which operates a shift fork
and push rod assembly.
• A shift fork and push rod assembly which engages
and disengages the differential lock curvic clutch
assembly.
• A curvic clutch assembly which consists of a sliding
clutch splined to a axle shaft and a fixed clutch which
is splined to the differential case hub.
The Differential Lock also includes a selector switch (electric)
which senses clutch engagement and sends an electrical sig-
nal to a cab mounted indicator light (or an audible signal
device).
Without Wheel Differential Lock
Lift the drive wheels completely off of the ground or damage
will occur.
Do not lift the front wheels (non-drive wheels). This alters
the oil’s position in the drive axle, draining it away from the
drive pinion and its bearings. If the pinion is rotated under
these conditions for any period of time, bearings will over-
heat resulting in axle damage or failure
If this is impossible to lift the drive wheels, remove all axle
shafts to prevent gear rotation and cap the wheel hubs to pre-
vent loss of lubricant and a possible road hazard. See the pre-
vious section “Proper Vehicle Towing with Wheel Differential
Lock” for removal procedure.
WARNING