Engaging The Power Divider Lockout - Mack Granite GU Series Operator's Handbook Manual

Inter-Axle Power Divider Lockout (If Equipped)
The MACK power divider can be rendered inoperative, during short periods of
poor traction, using a power divider lockout. When the power divider lockout
is engaged, both axles are locked together (in positive through-drive) for
maximum traction with no differential action between axles. It is not necessary
to stop the vehicle to engage the power divider lockout. The lockout may
be engaged while the vehicle is moving at less than 30 mph, as long as the
wheels are not spinning.
CAUTION
Do not engage the power divider lockout if the wheels are spinning.
Note: Even when no traction is available at the spinning wheel, the driver can
"feather" the brakes (apply the brakes slightly), creating enough resistance at that
wheel to allow power to the axle with traction. Feathering brakes should not be done
with power divider lockout engaged.
Note: For vendor axles, see the vendor manual furnished with the vehicle.

Engaging the Power Divider Lockout

Normally, the Power Divider switch is in the OUT (disengaged) position. In
poor traction conditions, it may be necessary to provide positive through-drive
to both axles by flipping the switch to the locked (engaged) position.
1. Push switch to engage.
2. Momentarily release the accelerator pedal to allow the shift to take place,
then drive through the slippery area.
Note: A lockout indicator lamp will remain lit as long as the lockout is engaged. This
is to remind the driver to release the lockout as soon as normal traction is regained.
3. When driving conditions permit, unlock the power divider by moving the
Power Divider switch back to the OUT (disengaged) position. Then release
the accelerator pedal momentarily (to shift out of the locked position) and
drive as usual.
CAUTION
OPERATION 235