A powertrain for a vehicle includes an internal combustion engine and a transfer case. The transfer case includes a primary output shaft, an electric motor, and a planetary gear set. The primary output shaft receives engine torque from the internal combustion engine. The electric motor includes a rotor and a stator. The planetary gear set includes a sun gear rotatably fixed to the rotor, a ring gear, planet gears arranged radially between and engaging the sun gear and the ring gear, and a planet carrier coupled to the planet gears and rotatably fixed to the primary output shaft. The ring gear is selectively groundable for selectively transferring torque between the electric motor and the primary output shaft.