Bs I had a 2000 ctd 4x4 with the NV4500 trans. It had 100 hp bully dog injectors and a tst comp box.oh it also had.3.54 gears. I really miss that truck.but any way my truck on the interstate would get 21-22 mpg easy.putting in the 100 hp injectors made a big diffrence. Oh I got 16 mpg towing my wife's 98 dodge durango back from Kansas runing 70-75 would of got better I think if I kept the speed around 60 to 65.

Ok next truck I had was a 2004 quad cab 4x4 with the 5.9 and NV5600 trans. It had 3.73 gears.that truck was 100 percent bone stock.I towed my 3600 pound 65 Plymouth to kana city race way for the weekend.I live around 2.5 hours from there and I have a lot of hills etc.but back on track it was hot that day and I was having charging problems on the 65 plymouth.so I used the truck all weekend to keep cool and charge the car battery.even used the truck to drive around town. I never filled the truck up till after I got home and got 19.6 mpg. All these mpg figures were all done pin to paper.by that I mean I didn't go by what the over head said.

Ok next truck 2009 dodge crew cab 4x4 with the six speed auto.it had the dpf delete 5 inch turbo bax exhaust and a 500 hp EFI tune.I was on winter fuel and would get around 19 to 20 with it but didn't do much towing with it.

My 2011 3500 dully 4x4 crew cab long bed got the worst fuel milage of any of my trucks.it was deleted tuned etc and just driving on the intetstate it would only get 17-18 but it didn't matter what you had behind it man would it pull.

I can't say for anybody elese but after towing with a 93 dodge 1/2 ton gas truck a 2012 chevy 1/2 ton gas truck and a ford 300 six 1/2 ton truck.after towing for the frist time with my old 2000 ctd truck I will never go back to a gas rig. But that's just me if a gas truck is what you like more power too you. Also on towing 10,000 pounds the most I have ever heard was some guys getting 10-11