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.