I have a 2012 Ford F150 that has started to slip (for lack of a better word), every time I come to a complete stop. It takes a few seconds, but then gunk! It just slips/jumps forward a little bit. Nothing after that. A buddy told me he thinks my U-Joint is going out. Can anyone else confirm this or enlighten me on what else it might possible be? I am by no means a mechanic, but I would like to have an idea of what it might possible be before I take it to one.