Abstract: A vehicle having a four-wheel-drive system including an auxiliary portion that has an auxiliary driveshaft and drive means between the auxiliary driveshaft arranged to releasably connect a second group of wheels to the driveline via a releasable torque transmitting device. The releasable torque transmitting device is operable to allow slippage of the input portion with respect to the output portions, thereby to vary an amount of torque that is transmitted to the second group of wheels.

Abstract: A motor vehicle having: a prime mover; first and second groups of one or more wheels; and a driveline to connect the prime mover to the first and second groups of wheels such that the first group of one or more wheels is driven by the prime mover when the driveline is in a first mode of operation and the second group of one or more wheels is additionally driven by the prime mover when the driveline is in a second mode of operation, the driveline including an auxiliary driveline comprising releasable torque transmitting means operable to connect the second group of one or more wheels to the prime mover when the driveline transitions between the first mode and the second mode, wherein when in the first mode the driveline is operable to transition to the second mode responsive to an output of a reactive evaluator and a predictive evaluator.

Abstract: A vehicle having a four-wheel-drive system including an auxiliary portion that has an auxiliary driveshaft and drive means between the auxiliary driveshaft arranged to releasably connect a second group of wheels to the driveline via a releasable torque transmitting device. The releasable torque transmitting device is operable to allow slippage of the input portion with respect to the output portions, thereby to vary an amount of torque that is transmitted to the second group of wheels.

Abstract: Embodiments of the present invention provide a motor vehicle having: prime mover means; at least first and second groups of one or more wheels; and a driveline operable to connect the prime mover means to the first and second groups of one or more wheels such that the first group of one or more wheels and not the second group is coupled to a torque transmission path from the prime mover means when the driveline is in a first mode of operation and both the first and second groups of one or more wheels are coupled to a torque transmission path from the prime mover means when the driveline is in a second mode of operation, the driveline including an auxiliary portion for connecting the second group to the torque transmission path from the prime mover means, the auxiliary portion comprising first and second releasable torque transmitting means and a prop shaft, the first releasable torque transmitting means being operable to connect a first end of the prop shaft to the torque transmission path from the prime move

Abstract: Embodiments of the present invention provide a motor vehicle having: a prime mover; first and second groups of one or more wheels; and a driveline to connect the prime mover to the first and second groups of one or more wheels such that the first group of one or more wheels and not the second group may be driven by the prime mover when the driveline is in a first mode of operation and both the first and second group of one or more wheels may be driven by the prime mover when the driveline is in a second mode of operation, the driveline including an auxiliary portion comprising a first releasable torque transmitting means, a prop shaft and a second releasable torque transmitting means, the first releasable torque transmitting means being operable to connect a first end of the prop shaft to the prime mover, the second releasable torque transmitting means being operable to connect a second end of the prop shaft to the second group of one or more wheels, the vehicle further comprising control means operable to co

Abstract: A driveline for a vehicle such that a first group of one or more wheels and not a second group may be driven by prime mover means when the driveline is in a first mode of operation and the second group of one or more wheels may additionally be driven by the prime mover means when the driveline is in a second mode of operation, the driveline comprising: an auxiliary driveshaft; a power transfer unit (PTU) operable by means of PTU actuator means releasably to drivably couple the auxiliary driveshaft to the prime mover means; and a releasable drive unit operable by means of drive unit actuator means releasably to drivably couple the auxiliary driveshaft to the second group of one or more wheels, the PTU actuator means and drive unit actuator means each being powered by means of a pressurised fluid medium, the fluid medium being pressurised by a common pressurisation means.

Abstract: Embodiments of the present invention provide a motor vehicle having: a prime mover; first and second groups of one or more wheels; and a driveline to connect the prime mover to the first and second groups of one or more wheels such that the first group of one or more wheels and not the second group may be driven by the prime mover when the driveline is in a first mode of operation and both the first and second group of one or more wheels may be driven by the prime mover when the driveline is in a second mode of operation, the driveline including an auxiliary portion comprising a first releasable torque transmitting means, a prop shaft and a second releasable torque transmitting means, the first releasable torque transmitting means being operable to connect a first end of the prop shaft to the prime mover, the second releasable torque transmitting means being operable to connect a second end of the prop shaft to the second group of one or more wheels, the vehicle further comprising control means operable to co

Abstract: Embodiments of the present invention provide a motor vehicle having: prime mover means; at least first and second groups of one or more wheels; and a driveline operable to connect the prime mover means to the first and second groups of one or more wheels such that the first group of one or more wheels and not the second group is coupled to a torque transmission path from the prime mover means when the driveline is in a first mode of operation and both the first and second groups of one or more wheels are coupled to a torque transmission path from the prime mover means when the driveline is in a second mode of operation, the driveline including an auxiliary portion for connecting the second group to the torque transmission path from the prime mover means, the auxiliary portion comprising first and second releasable torque transmitting means and a prop shaft, the first releasable torque transmitting means being operable to connect a first end of the prop shaft to the torque transmission path from the prime move

Abstract: In one aspect of the invention there is provided a motor vehicle having: a prime mover; at least first and second groups of one or more wheels; and a driveline to connect the prime mover to the first and second groups of one or more wheels such that the first group of one or more wheels is driven by the prime mover when the driveline is in a first mode of operation and the second group of one or more wheels is additionally driven by the prime mover when the driveline is in a second mode of operation, the driveline including an auxiliary driveline comprising releasable torque transmitting means operable to connect the second group of one or more wheels to the prime mover when the driveline transitions between the first mode and the second mode, wherein when in the first mode the driveline is operable to transition to the second mode responsive to an output of a reactive evaluator and a predictive evaluator, the output of the reactive evaluator being responsive to a determination whether an amount of wheel slip

Abstract: Embodiments of the present invention provide a vehicle (100) comprising: prime mover means (111); a first group (112, 113) of one or more wheels; a second group (114, 115) of two or more wheels; and a driveline (105) to connect the prime mover means (111) to the first (112, 113) and second (114, 115) groups of wheels such that the first group (112, 113) of one or more wheels may be driven by the prime mover means (111) when the driveline (105) is in a first mode of operation and the second group (114,115) of wheels may additionally be driven by the prime mover means (111) when the driveline (105) is in a second mode of operation, the driveline (105) including an auxiliary driveline (110) comprising an auxiliary driveshaft (123) and drive means (125) between the auxiliary driveshaft (123) and the second group (114,115) of wheels, the drive means (125) having: an input portion; a plurality of output portions each operable to drive a respective different wheel of the second group (114, 115) of wheels; a first re