How many miles before adding DEF
Senior User
Joined: Oct 2005
Posts: 256
Likes: 0
I have put 5 gallons in about every 6000mi.
The one thing I did learn is if you use the Ford stuff with the adapter that goes in def tank make sure you wash it. The last time I went to use it I noticed it had residual crystals in the filler nozzle.Needless to say I took a trip to dealer to replace it.
The one thing I did learn is if you use the Ford stuff with the adapter that goes in def tank make sure you wash it. The last time I went to use it I noticed it had residual crystals in the filler nozzle.Needless to say I took a trip to dealer to replace it.
Senior User
Joined: Jan 2013
Posts: 238
Likes: 0
From: Northern New Mexico
I waited for the oil monitor to recommend an oil change, so my first oil change was at a little over 7000 miles and the only indication I got about DEF was that the DEF tank was less than half full. About 1500 miles of the 7000 miles was towing my travel trailer. I'm more worried about running out of fuel with the 26 gal tank (about 22 gal useable) than running out of DEF!
Last edited by U235Fishin'; Jun 8, 2013 at 09:35 AM. Reason: Additional info.
Post Fiend
Joined: Oct 2002
Posts: 11,314
Likes: 4
is that true ?!? only 22 gal usable ?!?
then I've gotten a LOT lower than I thought WITH the 5er attached !!!
IIRC, I put over 20, maybe 24?, gallons in it when I wasn't paying attention on a trip up I-55 in the middle of nowhere
then I've gotten a LOT lower than I thought WITH the 5er attached !!!
IIRC, I put over 20, maybe 24?, gallons in it when I wasn't paying attention on a trip up I-55 in the middle of nowhere
Freshman User
Joined: Mar 2013
Posts: 31
Likes: 0
Miles between adding DEF
I've got around 5,000 miles on my new truck and haven't added any yet.
I have a couple questions for y'all.
1. Is there any kind of warning before the truck starts running in the reduced power mode (don't know the technical term)?
2. How many miles do you average between adding DEF?
Thanks,
David
I have a couple questions for y'all.
1. Is there any kind of warning before the truck starts running in the reduced power mode (don't know the technical term)?
2. How many miles do you average between adding DEF?
Thanks,
David
David, I travel a lot pulling my 5er. I can travel about 1000 miles before my Def. (ADD) light comes on, when that happens I refill it with a 2 1/2 gal of DEF fluid. It only holds 5 gallons.
Lead Driver
Joined: Jan 2010
Posts: 6,600
Likes: 84
I only recently hit 22 gallons filling my tank.
I had 24 MTE on the computer.
Low fuel alert (picture of a pump) flashed as soon as I pulled up to the pump.
There is no way I would go lower, I don't know why I allowed it to get so low anyways.
I had 24 MTE on the computer.
Low fuel alert (picture of a pump) flashed as soon as I pulled up to the pump.
There is no way I would go lower, I don't know why I allowed it to get so low anyways.
Senior User
Joined: May 2005
Posts: 327
Likes: 1
From: Columbia, MO
It seems that I get 800 to 1000 mi/gal DEF when towing and about 2000 mi when not towing. Most of my driving is 25 miles or more and not much stop and go. I pull a 33 ft 5-W camper for the towing that I do.
I just drove 700 miles...computer said 18.2 mpg, hand calculated was 18.0 driving 74 to 80 mph...I'm OK with this MPG, would like to get 20 mpg but truck not on full synthetic oil yet. 20 in tires, F-350 CC 4WD long bed, not bad.
I guess you could say that I am a happy camper.
BTW, filled DEF tank at a QT truck stop and I also filled up 3 empty 2.5 gal DEF containers so I'll have a supply...there is no bulk DEF where I live, and I try to fill up at Murphy stations when I can and they do not have bulk pumps. The $2.80 price per gal is much better than Wal-Mart $12.50/2.5 gal.
I just drove 700 miles...computer said 18.2 mpg, hand calculated was 18.0 driving 74 to 80 mph...I'm OK with this MPG, would like to get 20 mpg but truck not on full synthetic oil yet. 20 in tires, F-350 CC 4WD long bed, not bad.
I guess you could say that I am a happy camper.
BTW, filled DEF tank at a QT truck stop and I also filled up 3 empty 2.5 gal DEF containers so I'll have a supply...there is no bulk DEF where I live, and I try to fill up at Murphy stations when I can and they do not have bulk pumps. The $2.80 price per gal is much better than Wal-Mart $12.50/2.5 gal.
Post Fiend
Joined: Oct 2002
Posts: 11,314
Likes: 4
and it 'only' took 21.9 gal (but $78+ dollars thank you very much gooberment !!!!)
Senior User
Joined: Jan 2013
Posts: 238
Likes: 0
From: Northern New Mexico
The 26 Gallon Tank USABLE volume
The 'about 22 gallons' number is my number. I do not want to run the truck out of fuel ...... not good. Running out of fuel happens sooner if you are on a steep slope, but I am not sure if nose down or nose up is worse. I think I was as low as 23.5 gallons once, but I was driving on the interstate.
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Cross-Country
Joined: Jul 2004
Posts: 56
Likes: 0
From: Louisiana
I put in 2.5 gallons Monday, and it told me I had 500 miles to go. Tonight, Thursday, I put in another 2.5 gallons because I was below 99 MTE. WTF?? It steadily started counting down from monday like as if I dumped all the stuff on the ground instead of putting it in the tank.
This was my first time adding it, 7500 miles before needing any, and the first 2.5 gallons got me 250 miles. Something dont add up. I was beginning to think I had a 50 gallon reservoir for this stuff, now I read the tank is 5 gallons.
With all the technology in this truck, I would have expected better DEF level reporting\calculation. Even a sight glass under the truck would be OK with me.
This was my first time adding it, 7500 miles before needing any, and the first 2.5 gallons got me 250 miles. Something dont add up. I was beginning to think I had a 50 gallon reservoir for this stuff, now I read the tank is 5 gallons.
With all the technology in this truck, I would have expected better DEF level reporting\calculation. Even a sight glass under the truck would be OK with me.
Lead Driver
Joined: Jan 2010
Posts: 6,600
Likes: 84
There are only three sensors.
Full, under half and empty.
(Or maybe just Full and under half, I can't remember).
Anyways, you have to fill it enough to trip the full sensor.
Basically, fill up the tank.
At 250 MTE, I was able to add 5 gallons but you have to go slow near the end.
Best to fill in a quiet place so you can hear what's going on.
I agree, improved reporting would be nice.
BTW, 7500 miles is great. I get around 5,000.
Full, under half and empty.
(Or maybe just Full and under half, I can't remember).
Anyways, you have to fill it enough to trip the full sensor.
Basically, fill up the tank.
At 250 MTE, I was able to add 5 gallons but you have to go slow near the end.
Best to fill in a quiet place so you can hear what's going on.
I agree, improved reporting would be nice.
BTW, 7500 miles is great. I get around 5,000.
Cargo Master
Joined: Jul 2008
Posts: 2,569
Likes: 55
Just a quick note -
If you find a truck stop with the blue DEF signs at the pumps stop and fill up. It is quite a bit cheaper filling at the pump, and you don't have any jugs to worry about.
Another thought is I seem to remember using about 1.3-1.4 gallons of DEF on just under a 2000 mile trip. I hit the truck stop on my way out and again when I rolled back in to town. Not too bad. I had a load in the bed and my camper top/cap on, wasn't pulling a trailer.
Go back in the menu to Information and Exhaust Fluid. It will tell you what the level is (OK, 1/2, or 800 miles to Empty, not a real "meter" but it works). I usually wait until I see it under 1/2, but now that the truck stop across the street has pumps it is a lot more convenient.
If you find a truck stop with the blue DEF signs at the pumps stop and fill up. It is quite a bit cheaper filling at the pump, and you don't have any jugs to worry about.
Another thought is I seem to remember using about 1.3-1.4 gallons of DEF on just under a 2000 mile trip. I hit the truck stop on my way out and again when I rolled back in to town. Not too bad. I had a load in the bed and my camper top/cap on, wasn't pulling a trailer.
Go back in the menu to Information and Exhaust Fluid. It will tell you what the level is (OK, 1/2, or 800 miles to Empty, not a real "meter" but it works). I usually wait until I see it under 1/2, but now that the truck stop across the street has pumps it is a lot more convenient.