A device is provided which performs highly-accurate control in low-torque regions while taking advantage of hydraulic pressure sealed-type hydraulic control devices. The device includes: a first characteristic (sealed pressurization) obtained by closing the on/off valve and driving an oil pump: a second characteristic (sealed depressurization) obtained by disabling drive of the oil pump and opening the on/off valve; and a third characteristic (flow-rate control) obtained by opening the on/off valve and driving the oil pump. In the process of supplying hydraulic pressure to a piston chamber in a low torque region, the device performs control according to the third characteristic. In the process of pressurizing the piston chamber in a torque region higher than the low torque region, the device performs control according to the first characteristic. In the subsequent process of depressurizing the piston chamber, the device performs control according to the second characteristic.

To provide a device to facilitate protection of a clutch while minimizing degradation of the torque transmission performance. A hydraulic clutch for drive power distribution is provided between a drive power source and auxiliary driving wheels, and a commanded torque is determined depending on the travel situation. The hydraulic pressure corresponding to the commanded torque is supplied to the hydraulic clutch. The surface temperature of the clutch is estimated (detected). The device generates a limiting value to limit the commanded torque when the difference in rotation between input and output shafts of the clutch is not less than a predetermined threshold and the commanded torque is not less than a predetermined value and performs control so as to increase the limiting value with an increase in the surface temperature of the clutch.

A disconnect mechanism for a secondary driveline and method of assembly can be used in an all-wheel drive (AWD) vehicle having a rear driveline module (RDM) for changing drive modes between a two-wheel drive mode and an AWD mode. The disconnect mechanism can include a hydraulically actuated coupling clutch connected to a power take-off unit (PTU) for transferring rotary power from the PTU to the RDM during the AWD mode, a hydraulically actuated first and second rear clutch for rotationally connecting and disconnecting corresponding first and second rear axles drivingly coupled to rear wheels during the AWD mode and two-wheel drive mode, respectively, and a hydraulic actuating assembly including a source of pressurized fluid for actuating the coupling clutch, the first rear clutch, and the second rear clutch, and for synchronizing any speed differential therebetween.

A driving-force distribution device is provided that can supply lubricant to an above-positioned pinion gear among a pair of pinion gears even when rotation of a differential case of a differential mechanism stops in a two-wheel-drive mode of a four-wheel-drive vehicle. A driving-force distribution device mounted on a four-wheel-drive vehicle includes a differential mechanism and a clutch mechanism. The differential mechanism includes a differential case, a pinion shaft, a pair of pinion gears, and a pair of side gears. In the pinion shaft, a flow passage is formed through which a lubricant is allowed to flow from the below-positioned pinion gear among the pair of pinion gears toward the above-positioned pinion gear in the two-wheel-drive mode in which the pair of pinion gears rotate in opposite directions with the differential case not rotating. The lubricant is supplied to the flow passage by rotation of the below-positioned pinion gear.

A drive system for a vehicle for variable distribution of torque, from a primary input and secondary input, between a left wheel and a right wheel of a vehicle, the drive system includes a first and second torque output shaft, one for each of the left wheel and the right wheel, an open differential, and independently controllable first and second clutch packs, configured such that: torque from the primary input is transferred to each of the torque output shafts via the clutch packs; torque from the secondary input is transferred to each of the torque output shafts via the open differential; torque from one output of the open differential is summed with torque from one clutch pack output in the first torque output shaft; and torque from another output of the open differential is summed with torque from the other clutch pack output in the second torque output shaft.

A clutched device can include a differential and first and second conduits. The differential can transmit differential power to first and second outputs. Clutch plates can rotate through a clutch cavity and transmit power between the second output and a third output. An outer carrier and an inner carrier can be coupled for rotation with the second and third outputs, respectively. The first conduit can be open to a first peripheral region of the clutch cavity and fluidly couples the first region to a cavity separate from the clutch cavity. The second conduit can be open to a second peripheral region that is circumferentially spaced apart from the first region. The second conduit can fluidly couple the second region to a central region of the clutch cavity. Rotation of the outer carrier in opposite rotational directions slings lubricant to the first and second conduits, respectively.

An all-wheel drive vehicle driveline can include an input member, differential, pump, first clutch, valve, and second clutch. The differential can include a case member, differential gearset, first output, and second output. The differential gearset can receive input torque from the case member and output differential torque to the first and second outputs. The pump can pump a fluid to a first conduit. The first clutch can transmit torque between the input and case members when a pressure in the first conduit exceeds a first predetermined pressure. The valve can couple the first conduit to a second conduit. The second clutch can couple the case member to the first output for common rotation when a pressure in the second conduit exceeds a second predetermined pressure. The valve can selectively permit fluid communication from the first conduit to the second conduit.

A vehicle differential assembly is provided. The differential assembly including a differential case rotationally coupled to a differential housing. A differential gear set is rotationally coupled to the differential case. A ring gear rotationally coupled to the differential case. A disconnect member operably coupled between the ring gear and the differential case. The disconnect member having a torque transmitting member movable between a coupled and an uncoupled position, wherein the ring gear is rotationally coupled to the differential case when the torque transmitting member is in the coupled position.

An open center flushing valve for a hydraulic system including a hydraulic circuit and a fluid flushing system, where the flushing valve has multiple positions that each include a fluid exhaust path through the flushing valve. Any of the flushing valve positions couples the hydraulic circuit to the fluid flushing system through a fluid exhaust path for that position. The flushing valve can include unpowered and powered positions. The hydraulic circuit can have two sides separately coupled to the flushing valve where in a powered position, only one side of the hydraulic circuit is coupled to the fluid flushing system through the flushing valve, and in an unpowered position both sides of the hydraulic circuit are coupled to the fluid flushing system through the flushing valve. In a powered position, the lower pressure side of the hydraulic circuit can be coupled to the fluid flushing system through the flushing valve.

A power transfer device can include a housing, first and second input members, first and second output members, a differential, and a pump. The housing can define a sump. The first input member can receive rotational power and rotate about an axis. The second input member can be meshingly engaged with the first input member and can rotate through the sump. The differential case can be drivingly coupled to the second input member. The differential gearset can transmit rotary power between the differential case and the first and second output members. The pump can be disposed about the first input member and can have an inlet, outlet, and pump element. The inlet can be coupled for fluid communication with the sump. The pump element can be drivingly coupled to the first input member and can pump the fluid from the sump when the first input member rotates about the axis.