I am looking for a tow vehicle for my trailer 3,500 lbs. and future T.T. 7k+ lbs. Currently I have a ram 1500 5.7 love it no problems but want something with some more capacity. Im looking for 5.6 mpg empty and towng. 5.0 towing mpg. Also any experience with the 6.4 hemi vs either XD engine.