Abstract: A four wheel drive system of a vehicle has a multiple disc friction type transfer clutch capable of varying torque transmitted to front wheels, a hydraulic circuit for varying an engagement force of the transfer clutch by supplying a fluid pressure to the transfer clutch, front and rear wheel rotational speed sensors, a sensor for sensing a turning radius corresponding to a steering angle, and a control unit for varying the torque transmitted to the front wheels by sending a control signal to the hydraulic circuit in accordance with a front and rear wheel speed difference, a vehicle speed and the turning radius.

Abstract: A steering compensator for providing resistance to movement of a steering system away from a preselected center position until a steering force exceeds a preselected value which may be varied remotely while the vehicle is in operation. The preselected center position may also be varied remotely while the vehicle is in operation by a trim mechanism. The compensator may be rotary or linear and the resistance force may be provided by a variable spring force and/or a variable magnetic force. Optional features include a liquid system for viscous dampening and an undercut seat and cam arrangement for centering without significant slack or overshoot.