If you want to know about the 6.4 vs the Cummins, there is a thread with lots of info about the 6.4 on the Cummins Diesel Forum. I have the 2014 Cummins and love it but the 6.4 hemi would work for me. I would go with the 4.10's for sure. I have herd they have less issues where the temps get <0 deg than the diesel. I tow 31 ft TT and about 7500 pounds. I get 12-13 towing and 21 bare on the hwy. Only get the diesel if you want or need the power cuz it does not pencil out in savings. The jury is still out on the resale values.