DEF at truck stops

[Trevor]

If the DEF at the truck stops was “ bad “ then there would be trucks sitting on the side of the road everywhere. That’s the only place trucks get their DEF. I don’t get mine there because of price,but I would have no problem if need be. If the truck stops were only fueling a couple of trucks a day then I would worry about the DEF. But at a busy one then there’s going to be a constant turn over. They are getting several loads of fuel a day,and probably a tanker load of DEF at least once a week.

[Jeff n Susan]

I personally use the truck stop DEF, simply because I believe all DEF is the same, but also, it takes a bit of plastic out of the stream. I'm not a tree hugger, but if I can do a small part like this, maybe generations on down the road will have it a "few jugs better."

[Daryles]

On my "to do" list is to learn C++ programming and reprogram the computer to do without DEF.

[Jeff n Susan]

Daryles,
I see your signature has an F350 Lariat. I am assuming this is a Ford truck. Check out the software FORScan. It is a software program for Ford vehicles. Its pretty good, and someone with an idea of how PLC's (Programmable Logic Controllers) work, its not to bad.
Please don't take me wrong and think I am insulting anyone, I'm not! The information is out there!

[PNW Fireguy]

Three years of DEF at the truck stops and no problems. Anything is possible however the DEF tanks at commercial truck stops turnover far more. frequently than the boxes on the shelf. Follow the related maintenance (filters, etc) and you should be good either way.

[Djgrimaldi]

I have been using Truck Stop DEF in my Powerstoke since May of 2022 which had 6 miles on it when received from dealer. I have never used boxed DEF and I have had no problems with our truck that now has close to 16,000 miles on it.

[JABURKHOLDER]

I have always used truck stop DEF. I'm already there for diesel. I go inside, $xx.xx on pump #x, diesel & DEF. Pump my diesel, flip the handle, pump my DEF, collect my receipt, be on my way.

I have found that it is cheaper at the truck stop pump than the 2 1/2 gallon box. Currently, the Autozone brand is $17.49 for the 2 1/2 gallon box. That's $6.996 a gallon. Fly J's in OH hover at $4.19/gal at the pump.

One caveat, I do carry one 2 1/2 box on long trips as an emergency back up.

[Cat320]

I just paid $17.99 for two and a half gallons of DEF, but only $9.99 for an 80 oz jug of Power Service...at a local farm and ranch store. PS is nearly double that at Wally World.

[Bierp]

Originally Posted by BB_TX

I have never heard of anyone having had a problem with truck stop DEF. Or bottled for that matter.

But I can’t help but keep wondering. Tankers put new DEF on top of any old still in the underground tanks. And next time the same. And next time ….. The percentage new vs old would depend on the amount still in the tank. As such the old is still there on top of the old old, on top of the old old old, …. The old DEF can never be completely eliminated simply by adding new, just continuously diluted. Still, apparently it is not a problem. I am sure I am just over thinking it. My little engineer brain does that often.

As I understand it, this is what you're supposed to do with pizza crust. A small amount of one batch is carried forward to the next, in perpetuity.

Obviously this is for smaller scale pizza processing. Also, I may be completely talking out of my behind here.

[Camp CA]

I also buy DEF from truckstops ocassionally.....never any issues.

[RetiredandRollin]

Wait, what's DEF?

LOL!!!! Sorry, couldn't contain myself. The OP asked a pretty simple question and was bombarded with technical jargon down to percentages, crystallization, ratios; instant headache for me. You guys have this stuff down to a science!!!

I get mine at Walmart or Advance Auto whichever is closer at time of need and away I go...

[jeepman71]

I had trouble once in 2016. DEF was bad and had to be removed. Place of purchase was Auto Zone.90% from truck stops since with no problem knock on wood.

[Randy E]

I have over 295,000 miles on the last two trucks combined. Only 1 time I have used store bought DEF. Every drop has been from truck stops. Never had a single problem with any of it. Also I did not see anything different with the 1 box I added from the store.

[Bill and Lisa]

Originally Posted by 1retired06

I have never had a problem. I buy at truck stops because of shelf life. Rapid turnover at truck stops.

Same here. Never had a problem

[laverdur]

I had a similar conversation with the service manager at my dealership. He said he recommended only Ford DEF and why would I want to risk damage to a $10K engine. My take, he didn't want to lose the business. There have been a couple times that I was quite a distance from a Ford dealer and needed DEF. I bought it at a truck stop and it worked fine. As others have noted, DEF is manufactured to ISO standards.

[pacbj]

All fuels and def take their suction from the bottom of the tank. Each liquid has it’s own specific gravity, so it’s not layering like oil and water when new fuel/def is delivered. Tanks also have agitators to alleviate separation. Now, a small percentage of what you get “could” be day one fluid due to mixing. I wouldn’t be too concerned. Stuff that’s on the shelf has a higher probability of getting old. Typically it’s cheaper at the pump as well. I would go for that…

[MaxwellD]

Originally Posted by rohrmann

DEF will have no impact on power or fuel mileage because it is injected into the exhaust stream just ahead of the catalytic converter, not into the engine. It works with the converter to reduce oxides of nitrogen in the exhaust.

Not trying to be a S.A., but since that is the case, why can't I just use something like ammonia water (?) in the DEF tank ? I will continue to buy DEF at the truck stops - never had an issue - but just wondering .

Max

[Cyride]

I have used DEF at the pump for 3years. When I purchased my truck I was advised by a gentleman to do the following. Buy your DEF at truck stops that get a lot of truck traffic and if you buy it off the shelf check the date code to make sure it is fresh! I have never purchased DEF off the shelf and have never had a problem. Because my truck is not a daily driver the only time I fill the DEF tank is when departing on a long trip (like 2000 miles round trip). My truck does not use a lot of DEF, on a 2,500 mile trip pulling my 5th wheel I’ll have just under a half tank when I get home. I would not buy DEF that is a year old!

[Cyride]

If I need to add DEF between trips I only put in a couple of gallons. DEF does have a shelf life! It’s been a little while since I added to the DEF tank but the price at the pump for me has been less expensive at the pump than off the shelf. Not sure why a Ford dealer would say it could damage the engine? Most the sales staff at my dealer have no clue of how to run a diesel!! I had to show a Ford service technician what the oil change interval was on my truck! She was going by the book on a gas engine so be careful 😬!!!!

[Pathfinder75]

Truck Stop DEF from the pump 70% of the time.

DO NOT understand some saying price higher at pumps.
Talking 2023 Central U.S.A. prices not last years.
Always find pump price between $3.60 and $4.50 so 2.5 gallon jug would be $9.00 to $11.25 at current prices rarely see below $12.00 then all the way up to $20.00 super good Blue Brand.
One farm store will have no name at $8.85 occasionally but I always check DATE CODE.
Mostly I don't mess with boxed anymore. Pump so much easier and I can fillup for a Trip.

Safe Travels and do what works for YOU #1