A power transfer unit is provided with a torque limiting coupling that
limits the amount of torque that can be transferred to the driveline
components when torque peaks occur while torque is transferred to the
non-slipping wheels. The torque limiting coupling includes an engagement
member disposed between an input from a driving member and an output to a
driven member. The engagement member is located radially between and
provides a frictional engagement between the input and the output. The
engagement member is capable of slipping under heavy torque loads in
order to protect the driveline components.