I have a new F250 and added my first tank of diesel to the truck today. I have been watching the DTE count down and planned my trip to bring it to about 15 miles before filling. Right at 37 miles the warning light came up and with 16 to spare I was adding diesel. Fuel gauge shows empty. Funny thing though, only 23 gallons went in. The pump stopped at 22 and I squeezed in about another gallon.

On one hand I was happy because I thought the mpg was really off based on the miles I had gone. Showing 17.4 on 400 miles. At 33ish gallons (what I thought it would take) I figured either the gauge was off, or perhaps the dealer hadn't actually filled it all the way up. Now I'm thinking it was the gauge.

So it brings me to my questions... is there a break in period for the fuel gauge? A few tanks thru before it reads correctly? I had a MINI that sort of did the same thing, it was only a 13 gallon tank but it took a little while for the gauge to read right and the warning light to come on at the 2 gallon mark and there actually be about 2 gallons in it.

Sorry if this is an old topic or covered issue. Thought this seemed a little odd and wanted to see if anyone else had a similar situation.

 

Short beds on 11+ have smaller tanks than prior years Super Duty trucks. This is due to the DEF tank that takes up the extra space. So what you filled up with is about normal to what I do with an almost empty tank.

 

The short bed truck only has a 26 gallon tank due to the DEF tank. The long bed is 37.5 gallon for same reason.

 

DTE and your fuel gauge are way off. Just like all of them. When my DTE reads 0 miles to empty, I have about 3-5 gallons still in my tank. It's just the manufacturer's way of protecting us stupid Americans from ourselves and running out of fuel...

 

Fill tank to the filler neck, as you found out you can squeeze another gallon in. Turn on, but don't start truck, reset one of the trip meters. Drive a least 200 miles and then fill it up the same way. Compare what you put in to what the meter says. Is this scientific, no.... But my trip meter is darn close to reporting fuel used vs. what I fill up with.

What I hate, is that you have a 26 gal. tank, but it doesn't mean that there is 26 gal. useable either. You'll start sucking air before using the entire 26 gals. I've had other vehicles that I drained the tank pretty good (and not on purpose)and ended up putting MORE fuel in that the reported tank size, but that isn't the case here.

At least Ford listened and made the tanks larger for the 2017's... Granted, I am not unhappy with the 37.5 gal capacity my long bed has, but the 26 gal tank in the short bed is too small, IMHO. If you get really tired of it, there are companies that make larger replacement tanks, but they are not cheap.

 

I agree with you. When I drop into double digits in miles to empty, I fill-up. 22 gallons is the most I've ever put in either of my SB trucks.

bruce...

 

Hey thank you for the info, this is great. That makes sense now why it seemed a bit short.

So does anyone trust the fuel used on the trip A/B option? If you reset it at the fillup, and later down the road it shows you use 12 gallons, do you believe that you actually 12 ish gallons, or is that even a little suspect?

 

I use the trip A/B option all the time. I reset it at each fill up and watch the gallons used more so than the DTE or anything else. With the Titan tank, I have covered 600 miles towing my travel trailer. It held the 60 gallons the trip B showed I used.

 

As I said in my earlier post I trust it. Enough that I rarely double check it any more. I am pretty much always at most .2 gallons off either way over hundreds of miles..

Here is the rub, how many useable gallons do you have? You won't know until the truck sputters and you look. And it isn't a good thing to let these rigs run out of fuel either, so that knowledge to me isn't worth it. On my long in the middle of nowhere drives, I usually (always up to this point) carry extra fuel with me in jugs. But I am fuel **** retentive.

 

Dak, I know on mine I can drive for 30 miles on "0 Miles to Empty" getting 9 MPG and it only takes 24 gallons at that point. Can I use all 26? Don't know. Maybe. I wasn't trying to find out the first time but got stuck in a huge blackout with no pumps working towing my RV two years back. Fun.

 

Been there with the no fuel or power at the stations thing. Had an '04 6.0 Excursion and put 50 gals in what was supposed to be a 45 gal tank. I don't remember how far past low fuel light we went.

Or could you use 28?

 

I re-calibrated my brain. I now consider driving past 0MTE as running on reserve...

 

When you get a 2017 you won't have to worry about as much, bigger fuel tank.

 

DTE empty, Fuel gauge and MPG are all an estimate and not are very accurate at that.
Once you get used to how much off they all are you're good to go.
I have the SB an just added a 33gal RDS aux tank to increase the range.

 

On mine, "gallons used" is typically 1.5 gallons optimistic over a tank full. If it shows I used 30 gallons (for instance), I will add about 31.5. Mine has done this consistently since new. Obviously, that also affects the mileage calculations as well, but my DTE is typically pretty decent.