hello everyone i have an 2004 f250 6.0 psd and i have an issue where its happen to me twice so far i been driving in the freeway and wen i go about half throttle about 80 mph the truck shutters or sputters so as if it loses power then it gets it back and it does that in spurts of every 2 seconds till i either slow down to 65mph or i go 3/4 throttle at 85mph so ihave no idea what it is