Is it the transmission?

My husband called me this morning and apparently our van died. We have a 2001 ford freestar. I have been pointing out for a few weeks that the car shudders every once in a while and he`s told me that it`s just the a/c. Idk if that helps. He said it lost All power and won`t go in drive or reverse. We replaced the alternator a few months ago and the torque convertor about a year ago. Does it sound the transmission? Any ides about what we can check before we have it towed and taken to a repair shop? I gave all the info I can think of.