A powertrain braking system for a vehicle includes an powerplant that can
be regulated to provide a desired powerplant torque and a transmission
that transfers the desired powerplant torque at one of a plurality of
gear ratios to provide a desired axle torque. A control module calculates
an axle torque command based on a powertrain braking request and
determines a shift command based on the powertrain braking request. The
control module controls the powerplant based on the axle torque command
and the transmission based on the shift command to achieve a desired
vehicle deceleration rate that corresponds with the powertrain braking
request.