Somebody pinch me & wake me up...

[Bill-N-Donna]

Could this really be accurate? After a couple trips to the dealer and much needed work the truck the onboard computer was indicating 18.9 MPG average while traveling at 55. After the 55 MPH limit I was traveling at 65 MPH then it dropped into the 17 MPG range. When I got back home after a round trip of 331 miles I’m showing 17.4 MPG on the computer. My tank is showing slightly under half. I keep expecting to wake up and find this not a reality.

I had someone tell me once that “figures don’t lie but liars know how to figure.” Well I filled the tank back up at the same pump and this is the figures I got. 17.685 MPG. Somebody pinch me and wake me up from this dream.

I’ve always heard that a 6.0 will only get about 12-13MPG, what is the best you’ve gotten with your 6.0?

[NCFischers]

Bill,
Try going uphill for a while. Downhill only miles don't count. My computer will tell me I'm getting 98 MPG at times but I tend not to believe it.
Jim

[H. John Kohl]

Bill,
I have posted before that Cummins did a study on big trucks and found the wind resistance took over from rolling resistance at 55 MPH so that could explain the drop with higher speeds.
Glad you are getting some nice mpg.

[Slufoot733]

You know, I'm beginning to think it's the fuel. My '08 F350 gets lousy mileage. My '99 F-250 got 17 on average. Lately my wife's car (2005 Ford Five Hundred), which usually averages about 21 mpg, has dropped to 17 or so. All maintenance has been done on schedule for each vehicle but the mileage still drops.
I THINK IT'S A CONSPIRACY!

[CORattler]

The only true way for me to understand what kind of mileage I'm getting is to do a hand calculation. The result varies depending on terrain, winds, weight being towed, profile of what I'm towing, tire inflation, etc., etc.
I call my on board mileage calculator the "lie-o-meter"
Mileage like you are getting is a wonderful thing and a good reason to smile. I'm happy for you!

[mtheo]

don't tell me you were towing your Monty

[brenkco]

Jay,
I agree, I couldn't believe the difference when I kept a manual log and calculated the mpg. Trip computer was much higher in my case.

Ken

[8e3k0]

The lie-0-meter works okay as an indicator but will not give true values. I always hand calulate each time I fill and values are logged since the day I took delivery of our truck. I enjoy listing to some owners saying they get "X" miles per gallon. When you ask if they have calculated the mileage, comment normally is " oh no, I go by the dash reading or by my fuel gauge on the dash"!
At the end of the day there are so many variables; were you pulling (2000 lbs or 25,000 lbs), was it windy, at what speed were you travelling, how much idling was involved, city driving or highway, on and on??
I also enjoy listening to the sales staff of new trucks; "20 on the highway and 18 in town, getting as high as 18 pulling"! They don't expand on what the truck was pulling.
Yes winter diesel is of a lighter viscosity to prevent gelling and does not contain the BTU value that summer diesel has; mainly the reason why our fuel consumed per miles attained changes with winter diesel to higher consumption.

[Trailer Trash 2]

I believe its the mix the refineries are using a lower octane will have less umph, I think the methane in gas is the problem for gassers as for diesel its the lack of parafin in the fuel. I can get 17 mpg out of my ram if I go 55 no trailer and all hwy driving in one tank which would be nice if it was that way all the time but being real I get 14 city if I dont hot dog it. 11 towing on a flat 10 on a hard pull. EPA restrictions are the reason the deisel is getting the milage we see now. what would our trucks get with all that stuff off.

[junglejim]

Bill, I normally get around 13-14 mpg in the city and 17-18 on the highway. Now when I am towing it depends on the terrain. It is about 10-11 in the hills and 12-13 on flat land.

You must know also I have a 4" performance exhaust from the turbo back with no cat and 4.30 gears. I believe these make a differance. The exhaust helps, but the gears hurt (not when towing though).

I normally don't drive faster than 60-62 mph, that's empty or towing. I find ecspecialy when towing that keeps my truck in the "sweet" spot, torque wise and keeps the egts lower.

[richfaa]

We have never found much difference between the on board computer and hand calculating. The secret is to fill the tank to the same level every time. If we are going to hand calculate we fill to the fill brim. Our 08 6.4 does 15 to 17 solo under nominal conditions. Brand of Diesel IMO does make a difference. Every time we use Valero Diesel our MPG will drop..

[CamillaMichael]

quote:Originally posted by NCFischers

Bill,
Try going uphill for a while. Downhill only miles don't count. My computer will tell me I'm getting 98 MPG at times but I tend not to believe it.
Jim

Jim, the trick is once your onboard computer reads 98 mpg, you turn it off and enjoy the tremendous mpg...I think that's how it works??????? Michael

[kingdaddy]

My truck (see sig) will show right around 20.5-21.2 pure highway miles at around 65-68 mph on cruise control.
I calibrated the trip computer for distance (adjusted for tire diameter with Smarty Jr.) and the speedo and odometer are now right on.
The trip computer still reads a bit high though...hand calculated closer to around 19 mpg! Yes, the on board trip compputers are often optimistic.
Best tank was just under 600 miles (stock 34 gallon tank) before I got nervous and refilled. Seems like it took about 31 gallons on refill as I recall.
I have 3.73 gears but with my tires the effective ratio is more like 3.55 or so. The mods I have do help the mileage especially considering the increased HP and torque. Considering the weight and power of my truck, I'm pretty happy with the mileage.
Looking forward to seeing what it does towing...

[BB_TX]

quote:Originally posted by Bill-N-Donna

..........
I’ve always heard that a 6.0 will only get about 12-13MPG, what is the best you’ve gotten with your 6.0?

My F350 6.0 SRW numbers run just a little higher than what you show. On flat open highway with no wind and running around 65, I can hold the computer at 20+. But I normally run 70 or slightly over and the mpg will drop to 19+ under the same conditions. But on most highways with curves and rolling hills and my normal driving, over long distance it will usually be between 18 and 19.
All this is not towing of course. Towing runs 10 +/- running 65-70 and depending on road and weather conditions.
I have on occasion checked the mpg with pen and paper and pump and odometer readings and have found my computer to give me about a half mile per gallon more that on paper.

[Bill-N-Donna]

quote:Originally posted by mtheo

don't tell me you were towing your Monty

I wish that were the case, which would really give me some bragging rights. I’m kind of anxious to find out if it’s helped while towing.

The recent motor work I had done seems to have made the biggest difference in getting the better mileage for me. I had 2 injectors replaced, 1 glow plug, a glow plug relay and an ICP control sensor. It had really developed a bad miss with the injectors dropping out.

I went to Mansfield, Ohio to pick up a car with my son. I simply kicked back and enjoyed the ride without being in a hurry.

[trfield58]

Bill, I have a 2006 F-350 Crew Cab with a 6.0. I have a 4" exhaust from the turbo back with no CAT. I also run custom tunes from Spartan. We take the Monty down to Myrtle Beach every fall to store it for the winter and head back down in the spring to pick it up (of course we stay there at least a week to unwind) Anyhow, that gives me a mixture of towing and "empty" mileage figures calculated by hand. Going down with just the truck, I average 18-19 MPG, and that is at 65 MPH. My brother has a stock F-250 with a 6.0 and he makes the trip with us. He didn't believe it, so he verified as I filled up each time and he is getting 15-16 MPG. Towing yields me slightly under 12 MPG traveling at 65 MPH. I really need to slow down because I know it's safer AND I'll get even better mileage. I currently have 55,000 on her and still running good. I'm really encouraged to see how many miles you have on yours...WOW.. I'm always nervous with this motor because of the reputation it has for EGR, Turbo and Head Gasket issues but I need to stay with this truck for at least a couple more years.

Good Luck,
Tim

[Bill-N-Donna]

Thanks for all the comments; it’s also encouraging to see other owners with the 6.0 tell about their engines & experiences. It’s true they have a bad rep but I was told by a diesel mechanic independent of Ford that they are really good engines and made by International. I believe how one takes care of them as to how well they will do. I don’t know the history of mine other than I was told it was a lot of highway miles. My dealer thinks someone really took care of it also. I’ve had to spend what I think is a lot on it for up keep and some unexpected things right after I first bought it but with the age and miles I expect some of that. I know right now I’m happy with it and its running better than ever since I’ve owned it. I hope to get another 1 or 200/k out of it.

[herewegotogether]

Bill
We have a 2006 F350 with 430 gears and get about the same. I really notice the defference when I get above 65 on fuel miliage.

[mlh]

I had a 6. PSD on the road I got about 19. With my 6.4 one time I got 99.9 MPG, then I got to the bottom of the mountain, Bummer. I think lotts of times people put something on their truck or put some giswhiz formula in their tank that they think will improve mileage, and then drive to prove it. My wife thinks her car runs better with a full tank of gas, and even jokes about it.
:ynwood