2014 F350 Lariat 6.7 Diesel
I am getting Range mileage of 457 miles and when I tried adding DEF the tank must be full because it overflowed. Anyone else experience the problem and can tell me how they resolved it.

 

Ford Dealer in Bozeman Mt resolved the issue as follows: Performed refill activation and parameter reset, messagecenter info light reset.

They charged me $198.29 to do the procedure and the diagnostics to isolate the problem.

 

Do you wait until it's near empty to do a complete refill? Or do you routinely or even every now and again top it off?

Most often the problem pops up when the DEF is topped off rather than waiting until it's near empty before filling. The system gets confused on the level and eventually gets to a MTE countdown.

This same problem happened to my own truck recently.

I always do my own maintenance and I only fill the DEF when it gets below 500 miles to empty. However I had shoulder surgery this year and ended up with my truck needing an oil change and fuel filters when I was unable to do the work myself. Took it to a dealer and had them perform all the maintenance.

Then not too long ago I had the DEF countdown come up. I thought nothing of it since it was about the right time and miles, so I started pouring in DEF. Couldn't even get through the first jug before it was full.

Come to find out the dealer topped off the DEF when they performed the maintenance. According to the miles it was probably close to the halfway mark when they filled it. The system never saw a refill and just kept the MTE countdown going.

I'm at 50K miles on my truck right now, and this was the very first DEF error it's ever had. And it happened at the one and only time time it its life when it was topped off.

That's my own experience. However there are times when the MTE countdown can go weird even when the DEF is being filled at the proper times. That's why I asked if you top off or wait to fill when you get the warning on the dash.

 

These systems are way too simple and fussy. On my 2017, I did the correct refill as Curtis mentioned above (filling and waiting until being alerted to refill) only to almost get shut down. I was coming home from IN to MA on a one day, 800 mile trip. About 300 miles from home I get a 500 MTE empty warning for my DEF. I say, no worries... I've got 200 miles to spare and I'll fill up in the AM. At about 200 miles from home, I get 100 miles to empty. What the heck? Ok, I'll fill up at a truck stop about 100 miles from home. I fill up and it doesn't reset. Not for 10 miles. Not for 20.... 30... OK, now I get a message that I'm going to be limited to 50MPH soon. Great. At least I'm only 50 miles from home. This is going to suck with 19k in tow after 12 hours of driving but at least I'm close. 50 miles comes and goes and I suddenly get a new message that I'll be limited to 50MPH at my next start up. Whooo hoooo. At least I can make it home at 70 and deal with this mess later. After 40 or so miles of driving with this message up, I get off the interstate about 5 miles from home. As I sit at the light at the end of the ramp, the message goes out and my DEF gauge suddenly creeps from empty to full. OMG, what a cluster. ON my next trip to the dealer I explain the scenario. They put a call in and get pinged back from Ford that this is a known issue on the 17's with no cure yet. Great... Anyways, not the same but an equally irritating issue with DEF....

 

I would get the ford fill spout. Then you won't over fill, important in the cold, and you won't spill either.


I too wait till <200 to empty, then do a complete refill. Mine has gotten confused once after a refill. I refilled it, message went away. Then a couple days later it came on. Since I just filled I ignored it. It went away the following day.