I purchased a 04 F-550 with a 6.0 Diesel from a individual. This truck only has 24,000 miles on it. Two weeks after driving it and pulling a trailer with bobcat, it started sputtering and coughing. Sucking down fuel and pouring out black smoke. Out of warranty because I am the second owner, I took the truck to a Ford Dealer and they said that it needed a new turbo. About $2,000.00. I then took it to a turbo mechanic and they said that there was nothing wrong with the turbo and started trying different options to correct the problem. Different Computer, no help. The last thing he did was install the original computer back and plugging in the wiring harness. Well this fixed the problem and everything was running perfect. One week later the same thing happened. turbo wasn't running and billowing black smoke. I unplugged the computer and reconnected and it seemed to be running fine again. This last for a day now. If I want to drive this vehicle I have to unplug and reconnect. Now it only last for a short drive. Can anyone tell me what I can do to resolve this issue. Thanks, Cosmickcarp