I currently tow a 30ft - 2011 open range roamer 303BHS (7100 dry) with a 2013 f150 ecoboost (previously a f150 v8)and we loved the design & floor plan as it was different than all the others at the ti...
Check Tongue weight, tire rating (LT not P) and pressure, perhaps shift weight to the front? Consider an Equal-i-zer or dual cam hitch (I just went to an Equal-i-zer). Funny story, I towed my Open Range all summer with the tire pressure mismatched due to a faulty electronic tire gauge. Once it was balanced out to the right psi it was night and day.