A lubrication system (400) for a transfer case (200) includes a pump (228) selectively supplying a working fluid to a fluid reservoir of an actuator (226) configured to apply force to a clutch assembly (214) to cause the clutch assembly (214) to move between a disengaged position and an engaged position. The lubrication system also includes a relief valve (302) having a relief valve inlet fluidly coupled to the fluid reservoir of the actuator (226) which opens to receive the working fluid based on a threshold pressure level of the working fluid in the fluid reservoir. The lubrication system also includes a trough (306) fluidly coupled to a relief valve outlet of the relief valve (302). The trough (306) carries the working fluid from the relief valve outlet to a bearing assembly (227) associated with at least one of an input shaft (204) and a primary output shaft (206) of the transfer case (200) when the clutch assembly (214) is in the disengaged position.

Methods and systems for a vehicle transmission are provided herein. The vehicle transmission includes an input interface configured to mechanically couple to a motive power source. The vehicle transmission further includes a first disconnect device releasably mechanically coupling a first output to a first drive axle and a second disconnect device releasably mechanically coupling a second output to a second drive axle.

An all-wheel drive system includes a center differential, a limited-slip differential clutch, a front-wheel torque transmission system, a rear-wheel torque transmission system, and a controller. The center differential distributes torque between front and rear wheels of a vehicle. The limited-slip differential clutch limits a differential operation of the center differential in accordance with an engaging pressure, and changes a front-rear torque distribution ratio between the front and rear wheels. The front-wheel torque transmission system transmits torque between the center differential and the front wheels. The rear-wheel torque transmission system transmits torque between the center differential and the rear wheels. The controller adjusts the engaging pressure based on a driving state of the vehicle. Reduction ratios of the front-wheel and rear-wheel torque transmission systems are set different from each other. The center differential is configured such that the front-rear torque distribution ratio is initially unequal and is changeable.

A product comprising: an axle shaft and an input shaft, wherein the axle shaft is coaxial with the input shaft; a clutch operatively connected to the axle shaft and the input shaft constructed and arranged to selectively couple and decouple the input shaft and the axle shaft; an actuator operatively connected to the clutch to drive the clutch; and a synchronizer operatively connected to the clutch to synchronize the coupling of the input shaft and the axle shaft.

A control device for a power transmission mechanism is provided, performing control so that a driving wheel reliably obtains torque when a vehicle is started. In a vehicle having a power transmission mechanism that includes a power transmission path transmitting power from a power source to a first driving wheel and a second driving wheel, and a power transmission element arranged in the power transmission path between the power source and the second driving wheel, a control device for a power transmission mechanism includes a control section controlling a fastening force of the power transmission element so as to control power transmission capacity of the power transmission mechanism from the power source to the second driving wheel, wherein when the control section acquires that the vehicle transitions from a traveling state to a stop state, the acquisition triggers the control section to increase the power transmission capacity.

A power transmission device include: a differential having three rotational elements; and a connection switching device that selectively switches a connection relationship among an input shaft, a first output shaft, a second output shaft, and the three rotational elements. Further, the connection switching device selectively fixes any one rotational element to a fixing member, the second power source is coupled to rotational elements other than the rotational element fixed to the fixing member, the differential can be switched between modes including a first mode where any one rotational element among the three rotational elements is coupled to the input shaft, one of the remaining rotational elements is fixed to the fixing member, and the other is coupled to the first output shaft, and a second mode where the three rotational elements are respectively coupled to the second power source, the first output shaft, and the second output shaft.

Provided is a torque control device for a four-wheel-drive vehicle that can stably output a minimum torque required to start or drive the vehicle to the auxiliary wheel side under a road surface condition that main driving wheels are stuck in the idling state or under a road surface condition equivalent thereto. When front wheels Wf1, Wf2 are judged to be stuck in the idling state, a current rear torque TrCMD is raised step by step. And, when a brake operates in the state in which the four wheels are at stop after raising the command torque TrCMD step by step, the command rear torque TrCMD is released. And, the command rear torque TrCMD is raised step by step when the command rear torque TrCMD continues to be released for a second threshold time.

An improved twin clutch, two-speed disconnect secondary drive unit, which may be configured as a rear drive unit (RDU) for an all wheel drive vehicle is provided. The RDU is driven through an input shaft, which is connected to a vehicle drive source such as a motor, and includes a twin clutch assembly, which is connected to the drive shaft and is selectively actuated to drive left and right main shafts, which drive respective wheels of the vehicle. The RDU further includes a modular a shift assembly mountable to one or both of said main shafts to drive output shafts, wherein each shift assembly is selectively operable between the hi-range and lo-range modes to shift driving operation of the output shafts between hi-speed and lo-speed operation. The shift assembly may be controlled by improved mono-stable or bi-stable actuators.

A vehicle includes a first axle, a second axle, a driveshaft, a first clutch, a second clutch, a third clutch, and a controller. The second axle has first and second half shafts. The second axle has first and second wheels. The driveshaft is disposed between the first and second axles and is coupled to the second axle. The first clutch is configured to selectively couple the driveshaft to the first axle. The second clutch is configured to selectively couple the first wheel to the first half shaft. The third clutch is configured to selectively couple the second wheel to the second half shaft. The controller is programmed to control the clutches to connect the second axle to the first axle via the driveshaft.

A drive torque transfer case is provided. The transfer case includes an input shaft, an output shaft, a gear assembly coupled to the input shaft, and a range clutch assembly coupled to the output shaft. The range clutch assembly includes a clutch member and a multi-piston actuator configured to receive a pressurized transmission fluid for selectively axially translating the clutch member to engage a component of the gear assembly for transmitting a drive torque from the input shaft to the output shaft. The multi-piston actuator includes an internal piston having a first annular surface area A1 and a third annular surface area A3, and an external piston having a second annular surface area A2 and a fourth annular surface area A4. The A1 and A2 are in hydraulic communication with a first hydraulic chamber, and A3 and A4 are in hydraulic communication with a second hydraulic chamber.