Presented herein are four-wheel drive systems incorporating a
bi-directional overrunning clutch design to control the torque
transmission between front and rear transaxles. In accordance with one
aspect of the present invention, there is provided a four-wheel drive
system comprising a front transaxle, a rear transaxle, a transmission
receiving drive power from a prime mover, and a bi-directional
overrunning clutch drivingly coupled to an output shaft of the
transmission and selectively coupled to the front and rear transaxle.