In a Ford crew cab DRW configuration you lose 995 lbs of payload capacity. Diesels have lots of advantageous including the ability to pull 30,000+ lb trailers up mountain passes. However, they are heavy and if you are hauling instead of towing they do impact what you can carry (if you care about GVWR).
Given that the gas engines can are rated to pull 15,000 lb trailers it shouldn't be surprising that they have plenty of power reserve to easily haul and engine brake a 5,000+ lbs truck campers.
I wrote a brief review of my experience after our first long trip.
Brief review of F350 6.2L and Af1150 combinationWe have added miles since then and been over a number of mountain passes in Washington, Idaho, and Montana since then. My experience hasn't changed except the gas mileage is getting better as it breaks
If you want a diesel go for it. Just do so with your eyes open.