Front Gearcase (Adc) Operation - Polaris RANGER XP 1000 2018 Service Manual

FINAL DRIVE
FRONT GEARCASE (ADC)

FRONT GEARCASE (ADC) OPERATION

The active descent control front gearcase is designed to
allow the vehicle to operate in 2x4, 4x4, or utilize the
vehicles EBS to allow 4x4 ADC (active descent control)
in the forward and reverse direction.
IMPORTANT
All-wheel drive ADC MUST be selected on the all-wheel
drive / ADC switch to activate the ADC system.
When the vehicle is in 2x4, all coils within the gearcase
are off. This allows the pinion and ring gear to spin
without engaging the front gearcase output hubs.
When the vehicle is in 4x4, the 4 wheel drive coil is
turned on but the ADC coil remains off. Turning on the 4
wheel drive coil applies drag to the outer armature plate.
The outer armature plate is connected to the roller cage,
which engages the rollers in the cage with the forward /
reverse ramp in the bi-directional clutch. In the event that
the vehicle wheels roll down a hill faster than it is being
driven, ADC will not slow the vehicle.
When the vehicle is in 4x4 ADC, the AWD coil is turned
on and the ADC coil remains off until necessary. When
descending a hill, the EBS slows the driveline and rear
wheels. The ADC coil detects the speed difference and
locks the front wheels to the driveline. The front wheels
can now assist in controlling the descent. Turning on the
ADC Coil applies drag to 2 inner armature plates. One
armature plate is connected to an output hub and the
other is connected to the roller cage. The frictional drag
between the two armature plates causes the output hub
to rotate the roller cage, which engages the rollers in the
cage with the forward / reverse ramp in the bi-directional
clutch. Because the hubs rotate faster than the driveline
in an engine breaking situation this combination of
events slows the vehicle when the clutch engine brake
system is active allowing true four wheel engine braking
in forward / reverse gears.
During engine braking the front drive can also speed
differentiate across the axle when turning. Also, if the
outer wheel slips or loses traction the inner wheel will
then begin to slow the vehicle as well.
9928487 R01 - 2018 RANGER XP 1000 Service Manual
7.30
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