To Tom Test out there in Okie country, thanks for the reply. It has some engine irregularities which may be what you described. I have it in a shop and although they have not seemed to get working on mine they suggested they had ruled out driveshaft issues, not sure if that rules out everything in the driveline. I am having difficulty getting anyone to get down and work on it. Ford sort of shirked it claiming tires out of balance. ( wasn't) amd did not more. I have had it at this truck repair place going on 3 weeks with no work yet.I was wondering if I went "up" in the Ford organization if I could not get some influence to make a local dealer really work on it. Another truck mechanic told me no one including Ford wants to work on them because many of the parts are different and time consuming to get ordered into the shop. Depressed Doug