So I have a 2017 250 with a 6.2, Crew Cab. Ford website says it has a 48 gallon tank? Filled up yesterday with 40 mi on the DTE. Only took 27 gallons. Computer said i was getting 12.4 mpg. Just talked to my service dept and they haven't had any other complaints. Guess I'll did into it more

 

Long beds have a 48, short beds have a 34. If it is a short bed have your dealer look up TSB 17-0046

 

Ahh, it is a short bed and they just called me back. They're ordering a new tank. Thanks for the assist

 

As near as I can tell, the 48 gallon tank holds around 50 if you fill it to the top (which is OK with diesel).

 

Taking 27 gallons with 40 miles DTE at 12.4 mpg suggests your fill-up at 0 DTE would have been ~30 gallons. Our truck's 34 gallon tank operates similarly.

I'll be interested in learning more about your truck's operational changes after the replacement tank has been installed.

Best of luck!
Jim / crewzer

 

So, after driving 15 miles past DTE = 0, I filled up this morning: 31.204 gallons. So, it looks like our truck's "reserve" is ~3.5 - 4 gallons.

Frankly, I'm not interested in having the new tank installed if the reserve ends up at ~zero gallons. However, if the reserve turns out to be ~2 gallons or so, then I might have it done.

Regards,
Jim / crewzer