The rating is the easy half of the answer. A trailer never weighs its brochure dry weight (water is 8.34 lb a gallon, propane and batteries ride along, and so does your gear), and hundreds of models changed their published weights mid-run, so the model year decides as much as the model. Judged that way, with a 10% margin and 2 people aboard: 5140 of 5150 campers fit a Ford F-250 Super Duty (6.7 HO diesel, gooseneck).
The number that quietly binds is payload, 3,535 lb (F-250 4x2 Regular Cab, 8-ft box, 6.7L H.O. diesel, 10,600-lb GVWR with Trailer Tow Pkg - the row Ford rates at 23,000 lb gooseneck): tongue weight lands on the rear axle with your passengers and the hitch, so a vehicle often runs out of payload well before it runs out of rating.
Loaded estimate: dry weight + full fresh tank + propane, battery and gear for 2. Headroom is against the rating less 10%.
THE HONEST SUMMARY
Fit, loaded, all years5140
Fit certain model years0
Too heavy loaded10
5140 fit. Which one is right for you?
That depends on what you care about: bunks for the kids, build quality, budget, weight you'd rather not tow. Set your priorities as sliders and watch all of these re-rank around them, live, with your vehicle already filled in. Nothing gets hidden.