Highly, highly recommend the Big Horn Ram V-8 5.7 litre Hemi
2014 or newer. Crew Cab and a medium bed.
I tow our 25ft Serenity up McNeil Canyon (Wa State) effortlessly, over the Passes like its not even behind me and plus the interior with the crew cab is just awesome for comfort. Back seat is huge plus turns into a bed.
If you can find it, the Ram Box option for storage is really cool.
The eight speed transmission is awesome and the heavy duty tow package, brake assist, etc is fantastic.
Have talked to some folks from the mechanical world about concerns with the 6cyl eco-boost and life expectancy for strength in towing. I would'nt take that gamble on a newer concept not yet tested by time.
If you are a Ford guy I would go with the Ford F-250 or save some $$ and get the Ram
1500, its worked great for me for 3 years now.. I love it.
Also highly recommend the Blue Ox for sway control.