Driving my Windstar at 80klms engine just cuts out, pull over, restart, runs ok

2007 Freestar w 75K 3 breakdowns Engine shut off while driving, towed each time to repair station. All reported car runs fine. Never found out the cause. The best answer I got was impending transmission failure that automatically shuts off the engine so it is not damaged. Cure......trade in for a Chrysler. P.S. I also had 2005 w tranny problems 2800 to repair and it went again.