As youre driving along the van will just die...

You have to put the key in the off position before you can start it again.

We recently had the transmission rebuilt by Mr. Transmission i think it was, and we took it back and they said they dont know whats going on. This never happened before the rebuild.

Anyone have a clue?

Have you had it chcked to see if there are any pinched wires?

Also the computer may have ben damaged electricly when the trans was replaced.

other than thoes 2 things thats all i have encountred my self.

I'd vote for changing the crankshaft and camshaft position sensors before I changed out the computer. These 2 items are much less expensive and cause exactly the symptoms you describe.