A vehicle power transfer unit assembly comprises an input shaft, an intermediate shaft at least partially surrounding the input shaft, a central shaft adjacent the input shaft, a peripheral shaft at least partially surrounding the central shaft, a first shift collar, and a second shift collar. The first shift collar is operable between a first position where torque is transferred from the input shaft to the intermediate shaft and a second position where torque is not transferred from the input shaft to the intermediate shaft. The second shift collar is operable between a third position where torque is transferred from the input shaft to the peripheral shaft and a fourth position where torque is transferred from the input shaft to the central shaft.

A vehicle control system to be mounted in a hybrid electric vehicle includes an engine, a center differential that includes a front-wheel-side output portion and a rear-wheel-side output portion and distributes torque outputted from the engine to a front wheel and a rear wheel, a limited slip differential mechanism that limits a differential between the front-wheel-side output portion and the rear-wheel-side output portion, and a motor disposed in a drive-power transferring system that transfers drive power from the rear-wheel-side output portion to the rear wheel. The vehicle control system includes a processor. When the hybrid electric vehicle is switched from a first traveling mode to a second traveling mode, the processor stops the engine while causing the limited slip differential mechanism to limit the differential between the front-wheel-side output portion and the rear-wheel-side output portion.

A vehicle has an engine, a limited slip differential (LSD) mounted on an axle driven by the engine, and left and right wheels operably connected to the LSD. At least one parameter indicative of a riding condition of the vehicle is determined. A slippery driving condition is detected based on the at least one parameter. The LSD is selectively locked in response to the detection. The slippery driving condition is detected when a torque requested by a user is above a load line of the engine, upon successive wheel slips occurrences, and/or when a wheel slip is detected while a preload is applied to the LSD.

Methods of controlling a tandem axle assembly in a vehicle, the tandem axle assembly including an inter-axle differential (IAD), one or more side gears, and a front tandem axle assembly having a pair of front tandem axle half shafts selectively connected to a pair of front tandem axle wheel hub assemblies. When a determined speed of the vehicle is greater or equal to a predetermined speed, the IAD may be locked, the tandem axle wheel hub assemblies may be disconnected from their respective tandem axle shafts, and/or the IAD may be moved out of engagement with the one or more side gears. When a determined speed of the vehicle is less than a predetermined speed, the IAD may be unlocked, the tandem axle wheel hub assemblies may be connected to their respective tandem axle shafts, and/or the IAD may be engaged with the one or more side gears.

A device and a method for operating a multi-axle drive train for a motor vehicle. A first axle and a second axle are operatively connected, at least temporarily, to a drive device. When the second axle is decoupled from the drive device and a request for multi-axle drive with a first value is present, the second axle is coupled to the drive device only when a noise-masking event occurs, or when the second axle is coupled to the drive device and the request for multi-axle drive is absent, the second axle is decoupled from the drive device only when the noise-masking event occurs.

A vehicle control system to be mounted in a hybrid electric vehicle includes an engine, a center differential that includes a front-wheel-side output portion and a rear-wheel-side output portion and distributes torque outputted from the engine to a front wheel and a rear wheel, a limited slip differential mechanism that limits a differential between the front-wheel-side output portion and the rear-wheel-side output portion, and a motor disposed in a drive-power transferring system that transfers drive power from the rear-wheel-side output portion to the rear wheel. The vehicle control system includes a processor. When the hybrid electric vehicle is switched from a first traveling mode to a second traveling mode, the processor stops the engine while causing the limited slip differential mechanism to limit the differential between the front-wheel-side output portion and the rear-wheel-side output portion.

Methods and systems for a locking mechanism in an inter-axle differential are provided. A vehicle system, in one example, includes an electric motor coupled to a clutch assembly in a locking mechanism of an inter-axle differential coupled to a first axle and a second axle, the clutch assembly is configured to selectively disengage the locking mechanism, and in the disengaged configuration the locking mechanism permits speed differentiation between the first and second axles. The system further includes an electric motor brake coupled to the electric motor and configured to selectively apply a brake torque to the electric motor and the electric motor is configured to actuate the clutch assembly.

A dual-motor transmission therefor, comprising a first and a second electric traction motor, a first gear arrangement, a second gear arrangement, and a summation box. The first gear arrangement includes a shaft and at least a first gear and a second gear, wherein each of the first and the second gears can be selectively engaged and disengaged with the shaft via a clutch, and the first gear arrangement supplies a first torque from the first motor to the summation box. The second gear arrangement includes a shaft and at least a first gear, wherein the first gear can be engaged and disengaged with the shaft via a clutch, and the second gear arrangement supplies a second torque from the second motor to the summation box, and the summation box is configured to combine the first and second torques and to output a combined output torque.

Methods and systems for a differential assembly are provided herein. In one example, a diagnostic method includes generating a clutch fault according to a variance between an initial engagement position and a lock point position of a clutch motor that occur during engagement of an interaxle differential (IAD) locking clutch coupled to the clutch motor. In the IAD system, an actuation assembly is coupled to the clutch motor and the IAD locking clutch.

A dual-motor transmission therefor, comprising a first and a second electric traction motor, a first gear arrangement, a second gear arrangement, and a summation box. The first gear arrangement includes a shaft and at least a first gear and a second gear, wherein each of the first and the second gears can be selectively engaged and disengaged with the shaft via a clutch, and the first gear arrangement supplies a first torque from the first motor to the summation box. The second gear arrangement includes a shaft and at least a first gear, wherein the first gear can be engaged and disengaged with the shaft via a clutch, and the second gear arrangement supplies a second torque from the second motor to the summation box, and the summation box is configured to combine the first and second torques and to output a combined output torque.