I have a 2004 f-350, and I have a vibration or kind of like a lugging on it between 80km to 100km and its only when I ease into it, I tried it different levels on the chip level one isn't to bad, level 5 is the worst the especially if you are going up hill. So I'm thinking the engine might be starving for fuel, or something is loose like a u-joint or something I have a fass pump the filters on that are new the one under the cab was changed but the one on top is kind of old. Front hubs were done I had the tranny transfer case and rear end just serviced so can't be any of those. If you can mabe give me some pointers or ideas id appreciate it.

Carrier bearing on the drive shaft, loose front wheel bearing, bad tire, engine dampener loose or damaged, fuel starvation, bad injector all come to mind.

Carrier bearing on the drive shaft, loose front wheel bearing, bad tire, engine dampener loose or damaged, fuel starvation, bad injector all come to mind. thanks man