A vehicle includes a differential gear that transmits rotation of a propeller shaft to an axle. A differential lock switches the differential gear between a locked state and an unlocked state. A clutch is provided in a power transmission path between a prime mover and wheels of the vehicle. A controller controls an engaging force of the clutch during a moving start of the vehicle in accordance with which of the locked state and the unlocked state is selected by the differential gear.

A vehicle includes a first axle temporary driven by a motor, a second axle permanently connected to the motor via a propeller shaft, and a sub-shaft that connects the propeller shaft and the first axle. A control system for a connection between the motor and the first axle includes a first clutch between the propeller shaft and the sub-shaft, a second clutch between the sub-shaft and the first axle. The first clutch is controlled to continue applying a synchronous torque until the second clutch is determined to be connected. The second clutch is controlled to be connected in response to a determination that the second clutch is connectable.

Methods of controlling axle torque distribution of a vehicle during steering through a curve include collecting, via a controller: input data which is representative of a plurality of vehicle inputs; vehicle data which is representative of axle torque of the front axle and axle torque of the rear axle; and constraint data which is representative of real-time constraints of the vehicle. The collected input data, vehicle data and constraint data are communicated to a predictive model. Determining, using the predictive model, whether torque adjustments are necessary. The distribution of the axle torque of the front axle and the axle torque of the rear axle is controlled, via the controller, when the torque adjustments are necessary as determined via the predictive model.

A behavior control apparatus for a four-wheel drive vehicle comprising a driving unit, front and rear wheel driving torque transmission paths that transmit driving torques of the driving unit to front and rear wheels, respectively, and control unit. The rear wheel driving torque transmission path includes a speed increasing device for increasing speed of the rear wheels relative to the front wheels and two clutches for the left rear w heel and right rear wheel disposed between the speed, increasing device and the left rear wheel and the right rear wheel, respectively. The control unit engages the clutch on the turning inside when the vehicle is in oversteer state during turning under braking in a situation where the two clutches are disengaged.

A powertrain for a vehicle includes an internal combustion engine and a transfer case. The transfer case includes a primary output shaft, an electric motor, and a planetary gear set. The primary output shaft receives engine torque from the internal combustion engine. The electric motor includes a rotor and a stator. The planetary gear set includes a sun gear rotatably fixed to the rotor, a ring gear, planet gears arranged radially between and engaging the sun gear and the ring gear, and a planet carrier coupled to the planet gears and rotatably fixed to the primary output shaft. The ring gear is selectively groundable for selectively transferring torque between the electric motor and the primary output shaft.

A method for operating a motor vehicle having a four-wheel drive and a drive unit, which can be switched on and off during travel, wherein the motor vehicle is driven by a torque provided by the drive unit, and the initially disengaged four-wheel drive is switched on, including: determining at least one limit torque which, while the four-wheel drive is switched off, can be transmitted from at least one wheel of the motor vehicle driven by the drive unit to the ground surface upon which the motor vehicle is travelling, while the slip between the at least one wheel and the ground surface falls below a specifiable threshold value.

A vehicle includes a tandem axle system having an inter-axle differential and clutching assembly, a forward or first axle assembly, and a rear or second axle assembly. The inter-axle differential and clutching assembly includes a differential mechanism having first and second side gears and a clutch mechanism having a clutch member and an actuator assembly. At least one of the first axle assembly and the second axle assembly is in selective driving engagement with the inter-axle differential and clutching assembly.

A method for operating a drive train of a transportation vehicle wherein the drive train is switched between a first operating state, in which a two-wheel drive of the drive train is activated, and a second operating state, in which a four-wheel drive of the drive train is activated. The drive train is switched by an electronic computing device from one of the operating states to the other operating state. During the driving of the transportation vehicle, a demand time is determined by the electronic computing device not later than which the switching from the one operating state to the other operating state must be completed, the demand time lying in the future with respect to the determination of the demand time. The switching from the one operating state to the other operating state is commenced at a starting time in advance of the demand time.

An eco-friendly vehicle and a hill descent control method therefor are provided to enable stable driving on a downhill road. The method includes detecting a downhill road inclination based on a request for hill descent control and determining an average inclination and an inclination variation width based on the recognized downhill road inclination. First braking force of a main braking source from a motor and a hydraulic pressure brake system based on the average inclination and the inclination variation width, and second braking force of an auxiliary braking source from the motor and the hydraulic pressure brake system for each driving wheel based on a target speed set with respect to the hill descent control and a speed of each driving wheel are determined. The first and second braking force are output by a corresponding braking source from the motor and the hydraulic pressure brake system.

A method for operating a vehicle having an all-wheel drive driveline with a disconnecting drive unit. The method conditions changing the operational state of the all-wheel drive driveline from a connected state to a disconnected state based in part on an operational state of a vehicle torque converter.