A drive axle assembly includes a pair of axleshafts connected to a pair of
wheels, and a drive mechanism for selectively coupling a driven input
shaft to one or both of the axleshafts. The drive mechanism includes
first and second drive units that can be selectively engaged to control
the magnitude of the drive torque transferred and the relative rotary
speed between the input shaft and the axleshafts. Each drive unit
includes a planetary gearset disposed between the input shaft and its
corresponding axleshaft, and a pair of mode clutches that may be
activated to cause the planetary gearset to establish different speed
ratio drive connections between the input shaft and the axleshaft. A
control system including an electronic control unit (ECU) and sensors are
provided to control actuation of the clutches so as to control the
side-to-side traction characteristics of the drive axle assembly.