Originally Posted by welbo97

there could be a couple of things going on. You may have gotten stuck in a regen. That is when the truck uses the def and extra fuel to burn out the diesel exhaust filter. It won't start a regen until it is warmed up and it takes at least 10 minutes of driving to complete, sometimes as much as 20. If you shut down before it is complete, it starts over next time. Driving around town, you can get stuck in that loop for a while. It really hits your mileage hard.
Here's real bad news... that mileage the computer is reporting isn't even as bad as the real mileage. I'm at about 40k on my 2012 and without fail, every fill up has taken at least a gallon more than the computer showed burned. I chalk it up to idle and remote start time. But the real number is miles driven divided by gallons added to the tank and I'm sure that's lower than my computer has been reporting.
As for additives, there wasn't much economic sense to paying $5/tank to save $2 in diesel (those numbers are made up but something to that effect). It's probably a good idea to run some through to help clean injectors or prolong the engine life somehow. But I'm betting this engine outlives me (and the truck body) anyway.

Originally Posted by Rlopez1229

So today I got new tires and changed my oil and both fuel filters. We'll see if the mpg improves any. Have any of you had any experience with archiol fuel additive? I've read a few good things about it.

Originally Posted by Rlopez1229

I'm sorry it's archoil fuel additive!

Originally Posted by Rlopez1229

I just recently purchased a 2014 f250 king ranch with 47,000 miles and I'm getting 13-14 mpg in city and highway no pulling and easy acceleration also no lights indicating something is wrong. This seems really low. Is there anything I can check or do to improve mpg? I feel like I should be getting more than that. Any help is greatly appreciated as I am new to the diesel world and looking forward to learning a lot. Thanks in advance

Originally Posted by Rlopez1229

I went with the non synthetic Rotella oil suggested by the diesel mechanic shop here in town. My truck is 4x4 and the hubs are in auto. The tires are also properly inflated. I think I'm going to stick with the motorcraft fuel additive suggested by ford. As for the as the chip goes I don't believe it has ever been programmed becuase there wasn't any other aftermarket parts on the truck. I would think if someone was to program it than it would've had alot of extras but instead the truck was completely stock. I think my truck is performing correctly the issue could be that I reset the mpg reader when I got the truck and again the other day by accident. Maybe by it being reset so soon it may take a while to get a true mpg reading average. Also on the trip A/B screen I'm showing slightly higher mileage thats what lead me to believe the reset has something to do with it. Thanks again for all your help so far!