Forum Discussion

allen8106's avatar
allen8106
Explorer
May 28, 2015

My Fuel Mileage

So I see a lot of posts regarding fuel mileage. Many of which are difficult to believe, such as "I get the same mileage towing my 20,000 lb. fifth wheel as I do not towing it". Personally I don't believe this and if you do I have some ocean front property in western Kansas I'd like to sell you. My "real" data is below.

I drive mostly 55+ mph to and from work each day, 62 miles round trip.
Each way = 4 miles at 30 mph on gravel roads, 12 miles at 65 mph, 15 miles at 70 mph.

I drive 65 or under while towing my 5ver.

2013 GMC 2500HD, long bed, regular cab, 4X4, 6.6L Diesel, purchased new.
2010 Jayco 31.5 RLDS, weighed 10,500 at grain truck scale a year ago coming home from the lake.

2,170 miles mostly towing - 11.29 mpg (75% or more towing)
2,763 miles some towing - 15.18 mpg (less than 25% towing)
27,499 miles no towing - 17.10 mpg

These numbers are based on actual numbers from 65 tanks of fuel between 10/19/13 and 5/28/15.

I don't have the exact numbers but in May 2012 my 2009 gas engine GMC averaged about 7-9 mpg towing to California and back, 3000 miles round trip, and averaged about 15-16 mpg when not towing.
  • itguy08's avatar
    itguy08
    Explorer
    Jun 01, 2015
    cbshoestring wrote:

    You people that "DIDN"T EVEN KNOW IT WAS THERE" scare the #@!! out of me. Please stop towing trailers, until you have learned to be 100% aware that you are towing a trailer, 100% of the time you are doing so. Your TV and the people around you, will appreciate your attention.


    ^^^ This. Knowing it's back there and putting that healthy fear of God into you is how you keep alert and safe.
  • badercubed's avatar
    badercubed
    Explorer
    Jun 01, 2015
    Driving style is the biggest factor.

    I used to only pull down 13.5mpg with my Ecoboost for daily driving (30mi each way to work with 80% on roads 55mph or faster). I am at 12.5mpg with my 6.2L F250 after 1,000 miles of the same driving.
  • tinner12002's avatar
    tinner12002
    Explorer
    May 31, 2015
    As for mileage, my 2015 is getting better mileage brand new than my 2012 after 37K miles so I'm happy with that. I purchased truck to work not to get super fuel mileage.
  • Slowmover's avatar
    Slowmover
    Explorer
    May 31, 2015
    Towing will exact a penalty of about forty percent where other factors are the same. Over 30% is a given, and up to forty is the range. Doesn't matter if it's a 1969 Trailer Life review or one from last week. Drag is drag. Some trailers are better by design than others, just as some drive trains are better than others when it comes to mpg.

    The average over a few thousand miles is what is worth watching.

    For general purposes the EPA average mpg will be close enough.
  • marcsbigfoot20b's avatar
    marcsbigfoot20b
    Explorer
    May 30, 2015
    4X4Dodger wrote:
    deltabravo wrote:
    ... on how the chip is programmed..


    Trucks, cars, etc haven't used a "programming chip" in many many years.

    They use a very elaborate computer, called an ECM to control the engine functions, which is far more complex than a "chip" of years ago.


    Yes and that ECM is made up of very specific Resistors, capacitors and integrated circuits (Chips)Flat mounted on a copper covered PCB (Printed Circuit Board) that get updated with software or FIRMWARE changes ie. RE_PROGRAMMED.

    Its the same thing.


    I think what some people mean is that on older vehicles you could open the ECM (computer) and take the EPROM chip out and replace with an aftermarket chip that has a different tune file on it. My 93 Blazer/Tahoe was like this.

    On my 2000 7.3 diesel I can reprogram or overwrite the stock ECM with a tune programmer.
    There is also a slot on the side of the ECM where you can mount an aftermarket mini circuit board with a tuned chip on it. This situation the chip overrides the tune on the ECM and uses the chip's tune. I have both, my ECM has been retuned with a Banks tuner, and I also have a 16 different tune shift on the fly chip....which is currently overriding the ECM tune.

    Most new cars don't have the to ability to change chip or add a chip, just to access the ECM tune file and modify it through the OBDII port.

    So there are a few different options depending on how old the vehicle is.
  • Mr_Beebo's avatar
    Mr_Beebo
    Explorer
    May 30, 2015
    On a truck forum I like to visit from time to time, there are always numerous threads about gas mileage, and how someone had added 40% better fuel mileage and the ability to smoke the tires in every gear but OD by having a "tune". The the argument begins over who sells the best "tune" (non musical). Guys will swear up and down, take cell pics of the mpg monitor on their dashboard, etc to prove their 2500 Dodge gasser knocks down 22mpg pulling a toy hauler thru Tennessee. Then the Chevy fanboy comes in and states his 6.0 and 4.10 gear gets 18 mpg with 4k of brick in the bed.
    No matter what they say, that annoying thing called physics just won't go away.
  • 4X4Dodger's avatar
    4X4Dodger
    Explorer II
    May 29, 2015
    deltabravo wrote:
    ... on how the chip is programmed..


    Trucks, cars, etc haven't used a "programming chip" in many many years.

    They use a very elaborate computer, called an ECM to control the engine functions, which is far more complex than a "chip" of years ago.


    Yes and that ECM is made up of very specific Resistors, capacitors and integrated circuits (Chips)Flat mounted on a copper covered PCB (Printed Circuit Board) that get updated with software or FIRMWARE changes ie. RE_PROGRAMMED.

    Its the same thing.
  • Bedlam's avatar
    Bedlam
    Moderator
    May 29, 2015
    The motorcycle mileage sounds about right. My ZG1000 usually gets over 40 mpg mixed driving, but the big tank lets me easily go 250 miles before I even start looking for a gas stop.
  • 1jeep's avatar
    1jeep
    Explorer II
    May 29, 2015
    cbshoestring wrote:
    1jeep wrote:
    Since April 1st I have been 42mpg going to work ....but that's on my motorcycle. Truck gets parked when spring arrives, I never bought a Prius so I don't check the mileage just add fuel.



    42 mpg, is that all :h

    I do not have a fuel guage on my '03 Sportster, so I just stop and add two gallon or so every time the trip odometer gets to about 120. Seems to work out to 50 mpg or so.

    If I take the little 50cc scooter toy, it gets close to 80mpg. But then my top speed is 45, and there are a couple hills around here that it will only do 20 mph. Which means I also get about 4 FPM (fingers per mile). :B


    considering I ride a kawi gtr1400 which puts down 164hp at the rear wheel and I don't ride like grandpa..i think 42 is pretty good. the tug boat Harley doesn't see 40 on a good day!
  • Bedlam's avatar
    Bedlam
    Moderator
    May 29, 2015
    2oldman wrote:
    And I never get tired of "I don't even know it's back there."

    I can tell you that when I tow my 20' enclosed trailer loaded at 8000 lbs with my Ram 5500 I do not feel the trailer at all behind me. However, I do see slower acceleration and quicker downshifts on grades. Towing the same with my Ford F250 I could feel the trailer resisting change of direction I made with the truck. I have a little flat bed trailer loaded around 2000 lbs that I sometimes tow with a VW Jetta - I can feel the trailer behind it because it does not have trailer brakes, but I cannot feel or even see it behind my Ram 5500 unless I am making a really tight turn.

    There are times that you get combinations that don't fight each other, but it is typically when the tow vehicle is heavier than the trailer (VW excluded on this one).

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