I have an 03 Ram 3500 5.9 HO. On the open road I get anywhere from 17-20 MPG. I towed my 14,000 lb 5th wheel yesterday and got 10 MPG at 65 mph. some people say that is good. Others say a 5.9 shouldn't drop that much.
2 Questions:
Which is right?

Will a tuner help increase towing mileage or does it just change power?

 

My present 1998, 24 V 2500 Dodge Cummins is about used up.The engine is still ok, but everything attached to it is failing. I have been looking at 2018 trucks and I am asking here for advice/experience.

I presently load the truck with a1500 pound slide in pop up camper , and pull a 3 horse slant bumper pull trailer with an equalizer hitch.

Total load is just shy of 16,000 pounds.Trailer loaded weighs about 6500#'s.Truck's curb weight isabout7500 #'s.
Will the new 2500 with a 6.4 L engine and auto trans pull it ? Will I need 4.10 gears or will the 3.73 do it?

My present diesel pulls it OK, but I and not a fan of diesels anymore.Too expensive up keep.

Specs on the new truck says a towing capacity of 17,080 #'s,but I know that is for the entire truck load and not just a trailer

 

I haven't pulled that heavy so I can't answer. I would want the 4.10 ratio. I have driven and towed with both those ratios and the higher ratio was much better towing. mpg between the two won't be much different. More important to have that ratio pulling like you are.

you hit it head on...even city transit is switching to gas from diesel on their small buses...to much $ to maintain...and your 98 didn't have def and dpf emissions. No way I would buy diesel...whatever you save on gas; you spend on fixing it.

 

Thanks PrimeM . Appreciate the reply