Polaris RANGER XP 1000 2018-2019, Service Manual

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9929399 R01 - 2018-2019 RANGER XP/ CREW 900/1000 Service Manual
© Copyright Polaris Industries Inc.
FRONT GEARCASE (ADC)
OPERATION, FRONT GEARCASE (4WDC)
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.
FINAL DRIVE