Toro 07390 Workman HDX-Auto, Service Manual

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Workman HDX Auto Page 8 − 3 Four Wheel Drive (Optional Kit)
General Information
Front Wheel Drive Operation
The Automatic on Demand front wheel drive feature on
Workman HDX Auto vehicles equipped with the optional
four wheel drive kit does not require operator activation.
The front differential on Workman Auto vehicles
equipped with the optional four wheel drive kit is an elec-
tro−mechanically activated bi−directional overrunning
clutch system. Front differential engagement is avail-
able when the ignition switch is in the ON position, the
transmission is in the low forward, high forward or re-
verse speed position and the accelerator pedal is de-
pressed. The front differential is dis−engaged when the
accelerator pedal is not depressed or when the trans-
mission is in the park or neutral position.
If a vehicle is equipped with the four wheel drive kit, pow-
er is not delivered to the front wheels until the rear
wheels begin to lose traction. When the rear wheels do
loose traction, the dual bi−directional clutches in the
front differential sense the rear wheels slipping and en-
gage the front wheel drive instantaneously to deliver
power to the front wheels. The front wheel drive system
continues to deliver power to the front wheels until the
rear wheels have enough traction to move the vehicle
without slipping. Once this occurs, the system stops de-
livering power to the front wheels and the handling char-
acteristics become similar to that of a two wheel drive
vehicle. The front wheel drive system functions in both
forward and reverse. When the front wheels are turned
for steering, the rear wheels will slip slightly more before
power is delivered to the front wheels.
When the accelerator pedal is released during vehicle
operation, the front differential relay is de−energized
which removes electrical current to the front differential
to disengage the differential (no power delivered to front
wheels).
Installation Instructions
The Four Wheel Drive Kit Installation Instructions
provide information regarding the operation, general
maintenance and maintenance intervals for the front
wheel drive system on your Workman Auto vehicle. Re-
fer to this publication for additional information when
servicing the front wheel drive system on your vehicle.
Four Wheel Drive
(Optional Kit)