[texan]

It would be somewhere between difficult to impossible in a full time awd car. Doughnuts are done through losing all rear end traction and maintaining front end traction, then simply keeping the nose in one spot while letting the tail rotate on this axis. A full time awd car is specifically designed to not make this possible, since all wheels will attempt to find tractive grip and you will just go forward. This is why you can easily powerslide an awd car through corners, but not do doughnuts.