My truck on occasion make a fluttering sound from the right front of the truck when under load pulling my camper. Will also do it without the trailer but easier to reproduce with the camper attached. Just got back from the dealer and a test drive with the diesel mechanic and after driving about 20 (with camper attached) I finally got it to flutter. Mechanic said it sounds like a Turbo Flutter coming through the air box that was very common on the 6.0L engines but has never heard of it with the 6.7L. Anyway he is calling FORD to see if they had an hits on this. Anyone else experience this????