First off we need or at least you need to know what size camper you are going to pull, how much it weights(not dry weight) and is it a 5er or a travel trailer. A 3/4 ton (F-250) is limioted to 5th wheel units pretty much 32' and down due to the limited GVWR and pin weight capacity.
Weigh the truck with full fuel, passengers and normal travel cargo and add 150# for a hitch.
Now find the GVWR (on the drivers door jamb) and the GCWR (in the owners manula) for you specific truck chassis, engine and axle ratio.
GCWR - loaded truck = max loaded trailer weight.
GVWR - loaded truck = max loaded pin or hitch weight.
you really need to have an idea of the cart weight before you decide on a horse to pull it with.
And number one rule...NEVER BELIEVE THE RV OR TRUCK SALES PERSON. The minute they see you on the lot with a diesel, does not matter if iti s a 3/4 ton or a 1 ton truck, they will have you headed off the lot with a 40' Teton.
As for trailer weights, you can plan to add 1000# or more to the dry weight with accessories, water, propane, batteries and your camping gear.
We get about 10 to 11 mpg running 65 to 70 mph with a GCW of almost 20,000#. We have a 4.10 axle. Solo we get 19 mpg at 55 MPH and 15 to 16 at 65 to 70 MPH.
Have fun looking...
Amateur Radio Operator (KE5DFR)|Full-Time! - 2012 6.7L Ford Crew Cab Dually -2013 HitchHiker Champagne 38RLRSB - Travel with one Standard Schnauzer and one small Timneh African Gray Parrot