Hey everyone, I just purchased a 2009 f250 4x4 diesel and I'm very concerned about the MPG (I bought the truck in San Jose Ca, about 113 miles from my home). I know that I'm not supposed to be concerned about the mpg when buying this kind of truck, but I wasn't expecting such terrible mileage. When I test drove the truck the electronic average mpg stated 14.2 so I thought that wasnt bad. I purchased the truck hooked up to my trailer and towed it home (approx.) 113 miles. I noticed that my mpg was about 9.5 (calculating by hand). Again, not what I was expecting but, I was pulling about 6000lbs in somewhat windy weather traveling south to north on highway 101. Also, had to deal with bumper to bumper, stop and go traffic for about 10-12 miles. When I got home and unhooked the trailer, I refilled my gas tank and reset the "average mpg". I have gone 25 miles and the electronic mpg says I'm getting 8.6 mpg. I feel sick!!! This is only driving in town (no highway), not getting the rpm's up over 2000 and keeping the turbo below 10 during take-offs. Will it get better, am I being paranoid, etc?
I am completely feeling sick knowing that I may have a truck that averages 8.5 MPG while driving around town. Is this possible, could there be something wrong?

 

6.4s are known for bad mileage

 

OK, mileage is going to suck, but don't rely so much on the truck to tell you what mileage it is getting. Those readouts are not truthful.

Hand calculate your mileage at each fuel stop, if you really want to know what your truck is doing.

The 6.4L Power Stroke is not known for for it's efficient use of fuel. Mostly that is due to the DPF, which occasionally dumps fuel into the DP system to make a hot fire and burn up the soot that has been collected.

With my small gas engine, I average about 14 MPG mixed driving (mostly rural highway). In town............I don't even look any more. Towing on the open highway, 10 MPG or a little less with an 8000+ pound load is average.

You should jump over to the 6.4L Power Stroke engine forum and read up on what other owners are getting for fuel mileage.

 

After a reset it takes the avg MPG sometime to give an accurate picture. In general the 6.4 is a humongous fuel hog! Just when the avg MPG starts looking good the engine goes into regen and that kills the mpg again. Comparing apples to apples i.e. axle ratio speed etc the 6.4l has worse fuel economy than the 7.3 or 6.0. Good luck on your purchase.

 

Thank you for the input everyone. I did read up on the 6.4L prior to purchasing, but nowhere did I read anyone else getting 8.5 mpg city. I just assumed I'd at least get 10-12 in the city...not 8.5. I'm hoping that I just checked the electronic "average mpg" too soon may get at least 1 or 2 more mpg.
I gotta deal with it now. May just get a small beater car for driving around town.

 

The digital read out has earned the name "lie-o-meter" for a reason. Dont fret until you hand calculate. And one tank is a terrible sample to base your decisions off of. Get several consecutive hand calculated MPG samples.

 

The 6.4 is a work hoarse, that being said if it's stock the mileage isn't very good. Many people get 12 to 14. Mine is a 2 WD, I get 17 during my weekly trek to work and back, last weekend went to Cleveland and with a combined work week and a 180 mile round trip to Cleveland it averaged 19. All I can say is most of the issues with this truck are with the DPF, not much you can do if your state does emission testing. Come over to the 6.4 forum and read up on maintenance upkeep and it will treat you good, except for the mileage.

 

I get around 13 city...but I don't do much city driving, I have a car for that. And my city is only 60K people. I can get 17 on the hwy unloaded.

7-9 pulling my 5er.

My lifetime average is 11.5 over 80K miles. I consider that to be on par with an 8K truck.

Takes alot of fuel to get that amount of mass moving. In addition you have the DPF.

Get something like a scanguage II so you can start monitoring your regens. If you are doing alot of city driving then you will need to know when in regen so you can just get it done and over with.

 

Thanks for the info, but I don't even know what a regen is? I would be thrilled if I got 11 mpg. I will research to see if I can figure out this regen thing though. Thank you

 

Regen is short for Regeneration of the DPF (diesel particulate filter). The DPF traps the soot so your tail pipes should be clean or maybe just a bit grayish at most.

You should not see any black smoke out your tail pipes.

Once the DPF is full a regen is started.

Process is an injection of fuel on the exhaust stroke is sent down the exhaust to the DPF to superheat it and burn the soot.

Very inefficient but that was the process industry wide that was developed. It has since been refined for later models.

How long or how often this regen will occur depends alot upon your duty cycle/conditions/fuel.

You will begin to learn about how often yours will regen as you drive it. There is a brief message that will say "cleaning exhaust filter" but it does not stay on so you reallly would not know when completed. That is the reason for a scanguage II so you can monitor it.

What you don't want is the fuel that is suppose to go to the DPF ending up in your crankcase. So if you know it is happening you can avoid the shutdown.

Once you get the hang of it you will be able to work with it.

 

Is a scanguage II difficult to install, will it improve gas mileage? I live in Ca, the emissions capital of the world. Will it still be smog legal?
Thank you

 

Dittos on tracking the mileage over a longer period of time. That number will incorporate more types of driving anyway and give you a better idea of your average consumption. Determine your baseline and any improvement you can capture will put a smile on your face and a few dollars in your pocket. Good luck. Keep us posted.

 

Scanguage II just plugs into the OBD port. It is not a tuner. You just remove before inspections.

To the best of my knowledge the only tuner that is emssions complaint for DPF on tunes in CA is Banks 6-gun for the 6.4.

There maybe others.

 

Thank you mike

 

8.6 sounds pretty low. It is true that if you want something good on gas, you don't buy an 8000 lb. truck, but with that being said, you want to get as much as you can out of it. Or at least I do. I just traded in my 2011 F250 with the gas 6.2L in on a 2010 with the 6.4 diesel. Now, I've only had it a couple of days, but so far (and these aren't hand calculated, just what the trucks are calculating) I'm averaging around 15 combination around town and highway. My 6.2 never got better than 12, not matter how easy I drove it. Pulling my pontoon boat (which isn't much of a load for a truck like this) down the interstate at 70 mph, it was more like 5-6 mpg. Mike Butler with 5 Star Tuning is right down the road from me. I plan on getting him to do the dpf delete as soon as I get the money. I've heard of some pretty substantial gains in mpg once that is done. He told me he did one for a guy who pulled a 3 car hauler with his and went from 8-9 pulling the trailer to around 15 after the delete. Might be worth checking into.