Spicer Tandem Drive Axles Service Manual D__R440, 460, 480, D_R461, 462, 463, 521, 581, 601, 651, 652, 653 - Manual (Page 116)

112
Control Systems
Direct Driver-Controlled System
The driver manually locks and unlocks the wheel differential,
using a cab-mounted air valve. The following description as-
sumes the system includes a cab-mounted air valve and a so-
lenoid valve as shown in the illustration. Operation is as
follows:
1. With control switch in the unlock position, the wheel
differential functions normally.
2. When the control valve is placed in the lock position,
the air supply solenoid valve opens and air pressure
activates the shift unit.The shift fork is moved to en-
gage the sliding clutch which, in turn, locks the wheel
differential.
3. When the control switch is placed in the unlock posi-
tion, air pressure supply to the shift unit is shut off
and air pressure is released from the shift unit. A
compression spring moves the shift fork to disen-
gage the sliding clutch from the flanged case half un-
locking the wheel differential.
1 - Quick release valve
2 - Dry air supply tank 80 - 120 PSI
3 - Rear axle wheel differential lock air shift unit
4 - Fuse or circuit breaker
5 - Fuse or circuit breaker
6 - Indicator light or audible signal 7 - Wheel differential lock selector switch
8 - Exhaust
9 - Wheel differential lock selector switch
10 - Indicator light or audible signal
11 - Power supply
8
9
1
10
6
5
3
11
2
7
4
• Engage only when traction is poor.
WARNING !
This vehicle is equipped with the
Spicer Driver Controlled Wheel
Differential Lock.
For further information
consult your owners manual
[publication #XX-XXXX]
Steering will be adversely
affected when engaged.
• Do not engage when tires are spinning.
• Disengage when going downhill.
DRIVE CAREFULLY
WHEN ENGAGED
• Disengage at speeds above 25 mph.
Disengaged
Engaged