This is a very vague statement and crude thought process. Part of my background is in diesel power generation. Engine runs, spin armature in a winding case, makes energy power. Simple concept, but when something goes wrong and diesel engine runs backwards, the armature spins backwards and it becomes the motor and keeps the engine spinning. WHAT IF? - there was some sort of "gear box" between the front axle and the "motor"? Under normal driving conditions, most cars only use 2 Wheel drive. This concept could use the front axle motor to run backwards and "generate power". Then when need arises, gear box changed the direction and it becomes a drive motor for the AWD action. What do you think?