Driving on Hwy and heard a noise and felt small bump. Pulled off Hwy and stopped felt like a flat. Looked at all tires but could see no flat. Looked under truck and could see nothing wrong. This was all done with a flashlight as it was night and a very dark area. Drove about 100 yards to Hwy and stopped at stop sign,turned right and in about 30 ft. Big thump stopped on shoulder and looked with flashlight and found right rear tire and wheel twisted completely off and tire on wheel well was all that was holding truck up. Thank god I had stopped to look so there was no accident. This could have been a disaster if I was travelling at Hwy Speed. Towed to local Ford dealer and they are doing repair so not sure of exact cost but was quoted $550 for new wheel plus new studs and lug nuts plus labour. Until I googled this I did not realize it has happened to others and some more than once. What Now? We do not feel safe driving our new (to us) truck. Keep driving and fingers crossed and hope next time a tire and wheel fall off we are not on Hwy. Local Ford dealer assured us that all repairs were done and all wheels torqued and in good shape. Come on Ford this is a problem and you must do something. Ron