DEF usage?
Super Moderator
Joined: Aug 2008
Posts: 37,370
Likes: 1,858
From: Frederick, MD
my 2013 with the 5 gallon tank could go about 4500 miles with heavy towing.
My 2021 with 7 gallon tank goes about 3K towing same trailer. Has to do with all the increases in HP and TQ I would say.
When towing I switch the dash to read the def level and fill accordingly at truck stops. Fill at the pump since I am using it quicker than before.
My 2021 with 7 gallon tank goes about 3K towing same trailer. Has to do with all the increases in HP and TQ I would say.
When towing I switch the dash to read the def level and fill accordingly at truck stops. Fill at the pump since I am using it quicker than before.
Laughing Gas
Joined: Nov 2019
Posts: 852
Likes: 90
From: Florida
I'm glad I saw this thread. People I've talked to at the campgrounds keep telling me how little DEF they use. Towing our 41' Montana 5th wheel we use a lot of DEF. I learned the hard way, to keep 4 jugs available when towing. This past February (peak COVID times) we went down to Florida and out west. On the way down to Florida there was some sort of DEF shortage. At one point we were limited to 50 mph. When I finally found a place to buy DEF they only had 1 box which we paid $30 for the 2.5 gallons. Every time we stopped we looked for DEF, very few places had it. Very few truck stops would sell us any because the truckers needed it. The whole rest of the trip if I saw DEF on the shelf, I bought it. I bought so much DEF that I still have 3 boxes in my garage 
Cargo Master
Joined: Jul 2009
Posts: 2,710
Likes: 77
From: Central Florida
We stayed in Marco Island & Pensacola. We had problems finding DEF from TN all the way down to Ocala, where I was finally able to pick up 7 gallons. Once we were in Marco Island and not towing the 5th wheel, we found a few more boxes.
Tuned
Joined: Dec 2018
Posts: 351
Likes: 181
From: Dayton, Montana
When comparing DEF prices between jugs and the pump at a truck stop, don't forget to add sales tax on those jugs, it is built into the pump price.
I have been buying jugs at walmart, but they just recently went up on the price by a dollar, so now it costs more than at the pump after tax is added to the jug price.
I have been buying jugs at walmart, but they just recently went up on the price by a dollar, so now it costs more than at the pump after tax is added to the jug price.
I loaded up with 12 x 2.5 gallons from Costco ($9.99 for 2.5 gal) and it's kept in a cool insulated garage at homm. Taking 7 with us on the road to TX for winter. They'll be protected from sun under our Tonneau cover.
Lead Driver
Joined: Nov 2005
Posts: 8,442
Likes: 4,946
I stopped at the truck stop along my route that has it at the pump for $2.29 a gallon, going to try and plan to stop there each time I go by, even if I don't need much DEF.
Tuned
Joined: Dec 2018
Posts: 351
Likes: 181
From: Dayton, Montana
For BluDef is very cheap. Walmart carries BluDef for $14.60 here locally. $9.99 at Costco.
The route we take to Texas for the winter, DEF doesn't go under $3.50 a gallon at truck stops (unless you have a trucker biz card or until you hit Texas)
The route we take to Texas for the winter, DEF doesn't go under $3.50 a gallon at truck stops (unless you have a trucker biz card or until you hit Texas)
Lead Driver
Joined: Nov 2005
Posts: 5,212
Likes: 4,215
From: Kaysville Utah
Exactly what I do. Anytime I see that 1/2 tank or lower I topoff. Several gas station along my daily route have DEF at the pump. It's up to about $3.00 - $3.20 per gallon.
Lead Driver
Joined: Nov 2005
Posts: 8,442
Likes: 4,946
And, $3.50 a gallon is still less than a 2.5 gallon jug for $9.99, and then you have no jugs to fool with.
But, whatever floats your boat!
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Cargo Master
Joined: Jul 2009
Posts: 2,710
Likes: 77
From: Central Florida
Why so much trouble finding DEF? Every truck stop sells it at the truck pumps.
$9.99 is not cheap at all for 2.5 gallons, cheaper at the pump than that, and no issues carrying all those jugs.
I stopped at the truck stop along my route that has it at the pump for $2.29 a gallon, going to try and plan to stop there each time I go by, even if I don't need much DEF.
$9.99 is not cheap at all for 2.5 gallons, cheaper at the pump than that, and no issues carrying all those jugs.
I stopped at the truck stop along my route that has it at the pump for $2.29 a gallon, going to try and plan to stop there each time I go by, even if I don't need much DEF.
Lead Driver
Joined: Nov 2005
Posts: 8,442
Likes: 4,946
Now, many truck stop pump card readers will only accept specific fuel cards, but that just means you have to go inside and pay cash or swipe your credit/debit card at the counter before pumping the DEF.
But, they will sell you all the DEF you need.
Cross-Country
Joined: May 2006
Posts: 62
Likes: 33
From: Central Oregon
I've got about 9,000 miles on my 2022 now, and at least half of that is towing our ~8k lbs travel trailer. I have a Edge CTS3 gauge which shows me percent DEF injection in real time. I've noticed a consistent trend that if I allow the transmission to shift to 9th gear while doing about 65mph on the freeway, it uses nearly double the DEF as running in 8th gear at the same speed and grade. This is confirmed in the DEF estimated miles to empty in the gauge cluster. For the first ~5000 miles on the truck, I just let the trans choose the gear while towing in tow/haul mode. Now I regularly lock out 9th and 10th gear to save on DEF. I've seen no appreciable change in fuel economy. The engine is a little noisier with the higher revs, though.
Cross-Country
Joined: Nov 2021
Posts: 93
Likes: 31
I have my first ever diesel on order (F-450). Is there any advantage to which brand of DEF you use? I see that the SuperTech at Walmart is about half the price as the BlueDEF. Is this like asking which motor oil is better where some people swear one is the best and another will ruin your engine?
Super Moderator
Joined: Aug 2008
Posts: 37,370
Likes: 1,858
From: Frederick, MD
def is def. buy it wherever,check the cap to ensure it is sealed.
Heavy towing, use the truck stop def at the pump as you will use it quickly for long tows.
buy the ford fill spout so you don't over fill and leak all over the place when not towing.
Heavy towing, use the truck stop def at the pump as you will use it quickly for long tows.
buy the ford fill spout so you don't over fill and leak all over the place when not towing.
Laughing Gas
Joined: Feb 2004
Posts: 830
Likes: 16
From: sacramento
Still annoyed with how much def this thing uses, I was getting 2 mpg better than my 2018 before this 2022 started all its smog regen crap. Now its worse, If I were in a free state I would smog delete it. I know its a federal thing but there is no way the wasted fuel and def creates a net cleaner environment.
I am in CA, all the truck stops sell biodiesel so that means I have to drive the trailer up front for regular diesel and out back for the Def. Wasn't as bad when I got 5-7k miles per tank of Def, but now it looks like I am every 2k miles
I am in CA, all the truck stops sell biodiesel so that means I have to drive the trailer up front for regular diesel and out back for the Def. Wasn't as bad when I got 5-7k miles per tank of Def, but now it looks like I am every 2k miles