Cummins diesel + Aisin transmission heavy hauling MPG

Hello,

New Ram owner here just bought a brand new 2015 Ram 3500 Dually to tow a 20K pound 5th wheel. Once I am past the 5-8K mile breakin, what kind of mileage can I expect at 55-65 MPH? I know air resistance increases fuel consumption exponentially, so anything over 60 MPH is eating up fuel, but I am just looking for a ballpark. Most of the towing data I found in a quick search were for 5-10K pounds.

http://www.ramforum.com/showthread.php?p=1169962

"Before you think yer depressed make sure yer not just surrounded by assholes."
~ Ms. Sophia

Count on 8 and be happy if it's better.

I am hoping for 11 or better. We will have to see. I took the extra weight of the Aisin so I am already behind the curve.

Valhakar said:

I am hoping for 11 or better. We will have to see. I took the extra weight of the Aisin so I am already behind the curve.

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Yikes. My father has a 2012 with the MPG killers removed, tuned, exhaust, 4.10 gears and doesn't get 11 towing his 10k bumper pull toy hauler.

My father has a 2013 3500 dually. all stock he is getting 11mpg hand calculated at 65 with a 17,000 pound 5er. Pretty much all the truck is tow that camper so can't really get you any other type of mileages...

mine, a 2015 2500 i am getting 19 highway, 13 in town and 9-10 currently towing... but I also only have 2500 miles on my truck so i'd like to see mine go up as well.. Oh and i'm towing 12,000 pounds of fifth wheel (only through nasty rolling hills as of now)

avolnek said:

My father has a 2013 3500 dually. all stock he is getting 11mpg hand calculated at 65 with a 17,000 pound 5er. Pretty much all the truck is tow that camper so can't really get you any other type of mileages...

mine, a 2015 2500 i am getting 19 highway, 13 in town and 9-10 currently towing... but I also only have 2500 miles on my truck so i'd like to see mine go up as well.. Oh and i'm towing 12,000 pounds of fifth wheel (only through nasty rolling hills as of now)

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The Cummins and transmission needs 6-8000 miles to wear in correctly, you may get 1-2 MPG as you put miles on it.

That's one hell of a toy hauler! What kind is it?

Sent from my SM-G920W8 using Tapatalk

Well I towed our new Dutchmen 3970 toy hauler from Tucson to Western Arizona. It's just shy of 17k pounds unloaded.

Only 1200 miles on the truck so the engine still needs to wear in and loosen up.

10.2 MPG. Amazing how good driving trumps emission deletes.

-Dave

5ers usually get better mileage than bumper pull.

6.7 up through 2012 didn't use DEF, they used diesel to regen the DPF. Killed mileage. 12-13mpg empty with cruise set at 70 on 2012 DRW with 4.10. 17@70 without.

You might get to that 11. Cheers.

I am hoping for 12+ once its worn in. We will see.

If you ever feel the need to just give that truck away, I'll take it off of your hands, free of charge! Cummins with Aisin is some seriously heavy duty. Hope she works great for you!

drittal said:

5ers usually get better mileage than bumper pull.

6.7 up through 2012 didn't use DEF, they used diesel to regen the DPF. Killed mileage. 12-13mpg empty with cruise set at 70 on 2012 DRW with 4.10. 17@70 without.

You might get to that 11. Cheers.

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I'm going to disagree with you on this one.

we had a 36' bumper pull camper we pulled with our 6.4 hemi. The truck did an awesome job with this camper. Camper weighed 9,000 pounds loaded and the couple of trips i had taken it on I had a bed full of fire wood as well (500 pounds?) I averaged 9 mpg all four lane interstate and majority of it being flat. this trip was 4 hours one way on the interstate. The truck was able to hit overdrive but occasionally i opted to lock it out, with no differences.

We then traded that camper for our 5er. the camper is 36' long and weighs 12,000 loaded. nothing in the bed of the truck other than a stroller and some misc light weight stuff. The truck struggled to get out of fourth gear running 62 mph. the trip we took was the same interstate, same direction just not quite as far, only 2 hours one way. I averaged 6 mpg for this trip...

I assume with the added wind resistance of the front of the camper being above the truck and the whole dang thing being 4' taller than my bumper pull is what accounted for the issues...

Holy crap

That's good to know.

drittal said:

5ers usually get better mileage than bumper pull.

6.7 up through 2012 didn't use DEF, they used diesel to regen the DPF. Killed mileage. 12-13mpg empty with cruise set at 70 on 2012 DRW with 4.10. 17@70 without.

You might get to that 11. Cheers.

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They still use Diesel to regen the DPF. DEF, aka "Add Blue", is used to reduce NOx.