How well does the RAM 2500 6.4 Hemi tow?

All late model gas V8's (typically 400hp/400ft. lb) start constantly downshifting a gear when you start pulling much over 7,500 lbs. over rolling hills. Drive over steeper grades (i.e., 5-7%) and you'll be seeing the tranny drop as low as 3rd gear (sometimes 2nd gear if you're pulling 10,000 lbs). If you maintain speed, say 55-65 mph, in 3rd and 4th gear, these V8's are going to be pulling 3k-5k.

If you don't mind having a gas V8 perform all these acrobatics on hills and steep grades, then by all means go gas. If you do mind, then consider a diesel.