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RamGuy2500's avatar
RamGuy2500
Explorer
May 21, 2016

Cummins 6.7 mileage

What type of fuel mileage are you all getting with your Cummins and does it help adding cetane boost. I'm averaging 15 MPGs in mixed driving but I drive it pretty hard off the lights. :B Towing I'm getting around 10.5 to 11 on the interstate with a 11K fifth wheel. I should mention I got the 68RFE trans with 3.42 rear end.

I apparently suck at starting threads because my last two have been killed off. Maybe third times the charm.
Tow Vehicles

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  • Calicajun's avatar
    Calicajun
    Explorer
    May 21, 2016
    Our 2015 Ram 2500 4x4 get 20-21 mpg highway, 13-14 city and 10-11 towing a 31' trailer trailer.
  • Nicholsfamily05's avatar
    Nicholsfamily05
    Explorer
    May 21, 2016
    We have had our new one for about 2 months and the dash has been saying between 18-19 lately.
    Sits pretty good between there. I'm pretty easy on it from the lights. Harder on the on ramps as I like to be at highway speeds before the ramp ends.
    With our little trailer we were down to 16.5. It's 33 foot old camper frame we use to pull our ATVs. Not sure of the weight.

    We pulled our 11K once but had issues with the trailer brakes so we didn't get an accurate measure there.

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