Fuel Milage out of 05-06 6.0l
 

Hey guys I was thinking about selling my dodge and going back to ford I really like the 6.0 and am just curious about what most of you are getting on fuel mileage my dually with cummins is getting 13 mpg but I just love the ford body and the room and 6.0 diesel with the right parts is bullet proof. Any help thanks guys

Depending on cab configuration 2x4 or 4x4, auto or manual, etc... Could be anywhere from 13-18ish I'd say. I get 15 mixed driving with my SC/SB, auto 5R110, 4x4. Rarely do I drive to work without a few WOT blasts too... I'm sure I could get in the neighborhood of 17 or 18 if I drove a consistent 60mph on flat ground. The Ford's are certainly one of the heavier trucks. I bet my little truck weighs close to what your dually weighs.

Mines getting around 12 to 15 with lift and tires. Had it up to 18 mpg at one point.

I have 3 averages

1) I tell fellow diesel owners the truth which is 16-18 city/19-22 hwy
2) Non-diesel owners get told 23-25mpg
3) Hybrid owners get told 35-40mpg

Also keep in mind that some mods can get you a little bit more per tank...provided you can keep your foot out of it

I have a stock 06 king ranch fx4 all stock other than egr delete and can get 17mpg going 65mpg but it drops to 13 going 75. Also im new sorry about my bad pic.

if thats the truth thats CRAZY GOOD, i get 12-14 city/16-17 hwy

Yep. Its true that's all highway, using a calculator. Not the dash mpg thing. Oh it has 4 inch exhaust, no muffler. I don't know if that affects mpg. I bought it used, 150,000 miles, never towed anything, never mudded, never any problems. I love it!

Yours is believable Jones'n, that's usually what most get.

I agree, 22 is out of this world. How are you calculating mileage Diesel_Daddy? Don't ever sell that truck cause you wont find another 6.0 that gets that.

So why does mileage drop off so bad over 65mph? Is it due to gear ratio, air intake, turbo? Im new so any info will help out.

I could proly get 20 if i drove at 50mph, but who does that??? not me

Unless my math got mixed somewhere. I had a CHP buddy clock me when I was doing what the truck said was 70mph, turned out I was doing 76, plus 10%, so then I knew my trip meter was off by about 10%. I get a little over 600/tank and I've never put more than 32-33 gallons. Given the differences in reading I'm really getting 660/tank which is 20mpg/33gal. I also tend to do a bit of drafting when I can, never dangerously close though, 2-3 car lengths.

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That wasn't a 1 tank average either, that was over the course of 5 tanks going from Ventura, CA to Little Elm, TX and back, a total of about 3000 miles. I've always noticed MPG will kinda spike right after an oil change too.

the BEST ive done was 17.6(hand calc.) going 60-62mph..... IF i ever saw 20mpg at 70mph id shit a brick

No no no, I didn't average 20mpg at 70mph, we just used 70 as the test speed to see just how far off my speedo was. TX and back was an average of 60-65mph the whole way, 55-60 on the speedo.

Diesel Daddy, how are you filling the tank? Just filling it up til the pump clicks off? That's probably why your numbers are skewed.

x2, i know mine is accurate cause i fill it till its about to spill out, going til it clicks the first time is NOT accurate

It's most of the reason I don't even check anymore, never had the patience to sit there slowly filling for 15 more minutes to get it to the top. However, it is the only accurate way of calculating mileage.

Unless you drop your tank and do the harpoon mod!

i used to check all the time, but like you said its kind of a pain in the ass... now i just drive, if i was worried about mpg i would not have got a truck... now i think i get 10-11mpg cause of warm ups and i drive like i want.(FAST)

In that case I'm down around 17/18ish hwy, which still ain't bad

That's actually still pretty good. 18mpg in a truck this size and of this weight aint nothing to shake a stick at brother! :c:

Thanks guys for all your replies I think today I'm going to go Down to the ford house a try and pick up a 07 f-350 lariat 6.0 hopefully can talk them down more lol I think it's time to go back to my ford roots and sell the dodge I really really like the cummins engine cause for 100k miles the only prob I had with it was a lift pump. But now the truck is getting 13mpg when babying it not using it for its purpose and that's just not going to cut it. Well thank you all for all your input I'll post pics and updates later.

Just try to keep your foot out of it (not gonna be easy) even though these motors sound B*TCHIN' uncorked at the upper RPM range, not to mention if you add a programmer to the mix. On the highway is the only time I'm good, in town I'll delay the shift a few seconds to get a nice roar from the pipe and I rarely speed...now that doesn't mean I don't get up to the speed limit fairly quickly, I just don't go far over it. Lol.

Agreed, not quite anything like the sound of a tuned 6.0 turning over 4k rpms.... lol.:rocking:

Equally, if not more important, is knowing how to correct your speedo. Please keep in mind that these speedos are calibrated by Ford, NOT NASA! It's very simple, you only need to find the rate of change. Lets say you went from 265/75-16s to 315/75-16s.
width: 265/25.4= 10.433 315/25.4=12.401
aspect ratio(x2):10.433x1.5=15.649 12.401x1.5=18.601
rim dia :15.649+16=31.649 18.601+16=34.601
rate of change :34.601/31.649=1.093
So, your speedo AND trip odometer are off by 9%. Simply stated: 1.09X60mph indicated is 66 on Johnny Law's radar. 1.09X450 miles on the trip odometer is 491.85 miles traveled.

So what gear ratio will correct this? 3.73X1.09=4.065 ~ 4.11 would be close.

This is about as close as any of us can hope to get without some crazy Myth Busters lab test. Why do I do it? I'm a sicko and like basic math. :tttt:

Ever checked the speedo from Ford, it's off from the factory...

I set mine with my GPS and Autoenginuity, so my speedo is as close as possible (AE only let's you change tire sizes .25" at a time, so still hard to get dead on, but you can get reallll close).

Your math probably still works well for metric sizes, but for the tires with inch sizes... IDK. A 35" tire next to a 37" tire, and there is way more than a 2" difference. Air pressure will also play a role in the overall size of the tire. Best way to do it is to mark a spot on one of the tires (installed on your truck) and roll it forward and measure the distance on the pavement it takes for one full revolution.

You can play with diameter with air pressure, but you can NOT change circumference/revs per mile. "Ye ca'naw change the laws of physics, captain!"
I used the metric conversion for the goal of finding diameter. The conversion factor is the same for diameter as it is for circumference. By referencing rev per mile on tire rack, thats about the same error rate also.
Bluntly, that method is a tool to sniff out the 25mpg BS artists. That was half of my motovation for figuring it out.

the best that i got was 18 mpg but that was over a two day trip and it was all freeway driving and the best i get in town is 12 to 14