Disconnectable driveline for all-wheel drive vehicle

A drivetrain for an all-wheel drive motor vehicle, the drivetrain comprising:

• a primary driveline being adapted for driving a pair of primary vehicle wheels, said primary driveline including a first differential having a first differential case;
• a power take-off unit having an input shaft adapted to receive rotary power from said first differential case, an output pinion shaft, a transfer gear assembly drivingly connected to said output pinion shaft, and a disconnect mechanism, said disconnect mechanism having a mode collar coupled for common rotation with said input shaft and sliding movement between a first mode position and a second mode position, said mode collar is disengaged from said transfer gear assembly when positioned in its first mode position and said mode collar connects said transfer gear assembly to said input shaft when positioned in its second mode position;
• and
• a secondary driveline being adapted to drive a pair of secondary vehicle wheels, said secondary driveline including a propshaft and a rear drive module, said rear drive module including an input pinion shaft, a ring gear driven by said input pinion shaft, a ring gear housing fixed for rotation with said ring gear, a second differential having a second differential case driving a pair of output gears, a pair of axleshafts interconnecting said pair of output gears to said pair of secondary vehicle wheels, a torque transfer device operably disposed between said ring gear housing and said second differential case, and a limited slip clutch assembly operably disposed between said second differential case and one of said axleshafts, wherein said propshaft interconnects said output pinion shaft of said power take-off unit to said input pinion shaft of said rear drive module, wherein said torque transfer device is operable in a first mode to inhibit transmission of rotary power between said ring gear housing and said second differential case and in a second mode to permit transmission of rotary power between said ring gear housing and said second differential case, and wherein said limited slip clutch assembly is operable in a first mode to permit relative rotation between said second differential case and said one of said axleshafts and in a second mode to inhibit relative rotation between said second differential case and said one of said axleshafts.