I towed a uhaul trailer and my transmission slipped and I had to be towed. The o/d light was flashing before this occurred. I took it to ford dealer and they said trans got hot and it was ok. Is this car safe to drive or did I reck the trans.
I would, at the least, have all of the fluid changed (not just a pan drop).
When the O/D light started flashing, did the transmission go into 2nd gear (limp home mode). If so you are probably okey. If you let the slipping go on until the van would not go any more, the transmission could be damaged. Only time will tell.
As ‘tardis’ recommended, have the pan dropped; the debris examined; a new filter installed; and the rest of the fluid in the torque converter flushed. You may get lucky.