My brother is currently awaiting a tow truck on Plumb Lane in Reno, NV. Out of the blue, while he was driving normally, he suddenly lost all forward movement in the automatic transmission. Reverse is OK. We have no clue as to what might have happened. There were no discernible noises. All appears Ok under the hood. Does anyone have a clue what might have happened? Anything relatively simple? Like not having to pull the trans. Help!