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Discussion Starter · #1 ·
My 2012 4 door 4x4 6 speed is getting poor fuel mileage and I have no clue why. To be honest it never has gotten the best mileage. I have ran fuel cleaner a couple tanks ago and it didnt change but maybe half mile if that. It doesn't have the deletes done yet. I was just wondering if anyone else has had this problem before.

Thanks Branom
 

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Actually just had this happen to me over the last two days truck got decent mileage with just the dpf delete done and the egr unplugged maybe 13-14mpg but now I'm running 10 if I'm lucky even the real time meter isn't where it was when I would cruise at 60mph over the last month. Hoping it's just the 6-12 degree weather in NJ recently! Curious to see anyone's input also...


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Discussion Starter · #4 ·
I was getting 16.5 17 mpg running 70 down the big road. If I dropped it down to 65 I get closer to the 18 mark. Now I've been averaging 12 to 13 mpg. I got at least a 70 mile trip 5 to 6 days a week.
 

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Discussion Starter · #6 ·
It hasn't shown any that I have noticed. It was just kinda odd that it started doing it out of know where. I'm wondering if has something to with the exhaust filters. I work for john deere and I know when the tractors regen you get a light on the dash and the exhaust smells sweet. It could be me but I swear im smelling the same thing on my truck. And its like its doing it every few days.
 

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Try changing the fuel filter mine tanked in mileage I changed the filter and it came back.
 

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Go Packers
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Cold weather & winter blend fuel are the biggest culprits for poor mileage. 65mph and a bit less will net better mpg's. The faster the lower the mpg's.
 
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I have never got more than 14 MPG. I do have 4:10 gears. I don't expect much more.
 

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Same thing happened to me was getting 18 then all of a sudden the liar gauge was saying 12.5.

Reset it and drove a 100 miles and it went back up.

I did not notice it was in regen mode
 

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Actually just had this happen to me over the last two days truck got decent mileage with just the dpf delete done and the egr unplugged maybe 13-14mpg but now I'm running 10 if I'm lucky even the real time meter isn't where it was when I would cruise at 60mph over the last month. Hoping it's just the 6-12 degree weather in NJ recently! Curious to see anyone's input also...


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Mine has been the same way lately. Oil and fuel filters were changed less than a month ago.
 

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before deleted about 10-11 was best I could get daily driving, after delete I'm getting 17-20.1 depending on how I drive.
 

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Cold weather & winter blend fuel are the biggest culprits for poor mileage. 65mph and a bit less will net better mpg's. The faster the lower the mpg's.
The mpg's of my truck suck during cold weather and when the fuel distributor sells winter blend fuel. I see mileage similar to what you get during the summer but during the winter I see 10-12 mpg. My previous truck (Ford 6.4L) only got 9-10 mpg during the winter.

I don't know where you live but I think Camperman hit the nail on the head (as the old cliche' goes). You can view my fuel economy by clicking on my fuelly icon in my signature. I've tracked my mileage for about 15,000 miles.
 

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I bought my 2012 on Monday. Driving from Fond du lac to Minneapolis, I got between 16 and 18 depending upon my speed. I filled up yesterday at Fleet Farm with a winter blend and now I am getting between 12 and 14. It is currently -20 in Minnesota. Sounds like cold weather, winter blend fuel , and city driving are the current culprits.
 

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I was getting ok mileage, like 17.2 mpg on the hwy at 70mph. Then I had a "check Engine" light come on at 30l miles. I drove it around for a few weeks and then took it in to the Dealer. My o2 sensor was bad, so they replaced it and because of a Recall on the EGR, they re-flashed the computer.

Now thanks to the ReCal.

HWY at 65mph=16.2mpg
at 75mph=14.3mpg

City went from 10-11 to 9mpg
No load, just me in an empty truck.
These numbers are obtained in perfect weather conditions driving from Ca to Az in 65-80deg weather, so no cold weather issues whatsoever.

Oh well it's not like my 5.9, I miss the 21-22 hwy mpg.
 
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