HELP! DEF Issue?
Prolocutor
Joined: Jan 2009
Posts: 13,618
Likes: 1,245
From: Western MA
If you use the Ford Motorcraft spout, it will shut off when full and not allow spillage. I use the cheapie one that comes with the Supertech 2.5 gallon jugs from Wally World. I just listen. You can hear when it's getting close. Then just hold the spout out of the filler neck a bit and keep an eye on it. Don't try to top it off. If your at half a tank and put in a full 2.5 gallon jug, call it a day. You won't spill any that way...
Hotshot
Joined: Oct 2015
Posts: 19,687
Likes: 12,812
From: Wyoming
I fill my DEF tank when the gauge hits a little below half. I use a full 2.5 gallon jug and have no need of a spout that knows when the tank is full. I buy the Wal-Mart brand of DEF. No issues. It would be nice to be able to run it almost to empty to ensure that I don't have any "old" DEF in the tank. But I'm not willing to take a chance of having the issue than Rodney (Karl4Kat) did.
New User
Joined: May 2018
Posts: 23
Likes: 1
These problems and more are why I bought a 6.2 instead of a 6.7 (since I needed load carrying more than towing). Beside wanting the ability to travel internationally, the DPF and DEF plague all the new diesel trucks- Fuso's, Mack's, Dodges, Volvo's, Ford's- all of them.
The new diesels with DPF hate everything but high speed highway driving. Stop and go, idling, four wheeling, cold tempratures DEF fillings and etc.
Best way to cure most of DEF related bad signals are 1) Shut the truck down when filling up the DEF tank. 2) Get at least to quarter full before adding DEF. 3) Make sure your DEF is well above freezing before pouring into the tank and better yet would be after the DEF tank heater has been on for awhile.
The new diesels with DPF hate everything but high speed highway driving. Stop and go, idling, four wheeling, cold tempratures DEF fillings and etc.
Best way to cure most of DEF related bad signals are 1) Shut the truck down when filling up the DEF tank. 2) Get at least to quarter full before adding DEF. 3) Make sure your DEF is well above freezing before pouring into the tank and better yet would be after the DEF tank heater has been on for awhile.
Fleet Owner
Joined: May 2015
Posts: 21,195
Likes: 306
From: Near Salmon Arm BC
Some of my shop trucks are 2016 and 2017 diesels. I try to drive them as little as possible because I despise diesels. But its not always possible to avoid them, so I've experienced a few times filling up the DEF tank to not have it register that its been added to. But if I just keep driving them they eventually seem to recognize that they were filled up. Sometimes it takes 2 hours, and other times 2 days, but eventually they do.
Posting Guru
Joined: Nov 2002
Posts: 1,222
Likes: 4
From: Texas
Have had some odd resets on my '17 in the 30k+ miles--I always use the Peak DEF and add a jug at about the 1/2 full mark. The only time I had a real hiccup was in near-zero weather and I added the jug and it kept going down, even tho I knew it was at 3/4 or more. Eventually reset after about 10 restarts.
Prolocutor
Joined: Jan 2009
Posts: 13,618
Likes: 1,245
From: Western MA
Pour it in the hole on the right.
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Super Moderator
Joined: Aug 2008
Posts: 37,375
Likes: 1,860
From: Frederick, MD
filling the def is pretty much a nothing burger if you follow a couple of simple rules:
1. Don't fill until <200 to empty.
2. Use the ford fill spout so you don't over fill.
3. Use the hole on the right, it has a nice shade of blue vs green.
4. Be patient for a day or so if it doesn't reset. It will.
1. Don't fill until <200 to empty.
2. Use the ford fill spout so you don't over fill.
3. Use the hole on the right, it has a nice shade of blue vs green.
4. Be patient for a day or so if it doesn't reset. It will.
Prolocutor
Joined: Jan 2009
Posts: 13,618
Likes: 1,245
From: Western MA
It's bad thinking on a 17+ as there is a known bug with the countdown resetting. The 17+ trucks us a sonar type sensor to ping the volume in the tank. No need to wait to refill. In the older system with the probes, if you didn't wait til it was almost empty, sometimes you could confuse the system requiring a dealer visit. Now, from 17 forward, the opposite is true.
Super Moderator
Joined: Aug 2008
Posts: 37,375
Likes: 1,860
From: Frederick, MD
It's bad thinking on a 17+ as there is a known bug with the countdown resetting. The 17+ trucks us a sonar type sensor to ping the volume in the tank. No need to wait to refill. In the older system with the probes, if you didn't wait til it was almost empty, sometimes you could confuse the system requiring a dealer visit. Now, from 17 forward, the opposite is true.
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