Interesting article on def quality

[sheridany]

I was reading up on boxed brands of boxed brands of def quality compared to the pump. Prevost continues to recommend box def because of poor quality seen in some buses getting def at the pump. I know we have discussed this pretty extensively in other posts.
This is an interesting read.

Is All Diesel Exhaust Fluid (DEF) the Same? - Fuel Logic

Is all DEF fluid the same? Get insights on Diesel Exhaust Fluid differences and their effects on vehicle performance in this guide.

www.fuellogic.net

 

[Rd1]

Thank you for the article.

So this suggests their 2.5G can cover 750 miles?? Its been a while, I thought 2.5g Super Techs were good for half that distance. Its been a long while since I kept track of the mileage. I thought, as long as they are upto the standards, they all covered similar distances. Anyone uptodate on different brands covering different distances?
The price seems just about twice supertech. if it covers twice distance, may be worth it..

 

[sheridany]

@Rich W aka Dr. Def
Since you use box DEF for your rig, are there any brands that you favor over others? I will follow the Prevost recommendation and go with box DEF for now.

 

[Crazydog]

ANY brand of DEF will do the job since they are all required to meet a certain standard. I've used cheapo walmart DEF almost exclusively since 2019 in our 2017 Ram Cummins.
I have used Blue DEF and also the Blue DEF Platinum when the cheap stuff was out of stock and there is no difference other than price.

 

[team bradfield]

Same here, I think the DEF thing started with my Fords in 16 or 17, never a problem

 

[wildebill308]

It did not take them long to come up with additives to add to your DEF. Like Rislone DEF Crystal Clean.
Bill

 

[Crazydog]

It did not take them long to come up with additives to add to your DEF. Like Rislone DEF Crystal Clean.
Bill

Yup and like all other fuel and oil additives they are unnecessary and do nothing.

 

[Rich W.]

Thank you for the article.

So this suggests their 2.5G can cover 750 miles?? Its been a while, I thought 2.5g Super Techs were good for half that distance. Its been a long while since I kept track of the mileage. I thought, as long as they are upto the standards, they all covered similar distances. Anyone uptodate on different brands covering different distances?
The price seems just about twice supertech. if it covers twice distance, may be worth it..

I base my milage calcs on 300 mpg for trip planning but I get more like 375 with my ISB. Bigger engines will use a bit more. Volume used will be dictated by the NOx sensors (pre and post) in the SCR. It’s possible that “better” DEF will go farther although I’ve never seen any evidence or documentation on this, and my take is that any DEF that is 32.5% urea will do the same job converting NOx to nitrogen and water.

 

[Rich W.]

@Rich W aka Dr. Def
Since you use box DEF for your rig, are there any brands that you favor over others? I will follow the Prevost recommendation and go with box DEF for now.

I use only box DEF in the coach and buy mid range brands. I never buy the cheapest stuff that Walmart or Tractor Supply sells and I never buy the most expensive stuff with all the so called “beneficial” additives. Also I always buy in advance of a trip because it will be about 30% +. cheaper in a store than at a fuel stop on the road for the same product. The main thing I look at (after discounting the cheapest and most expensive brands) is the date code. I want fresh (recently manufactured) DEF that seems to have been stored in reasonably climate controlled conditions.

Also while most of the info in that article is good, this statement “In the long run, substandard DEF may cause corrosion and permanent damage to diesel engines and equipment, significantly impacting engine life.” is false. It can impact the emissions system components (although even that is questionable) but not the engine. All DEF effects occur in the last stage of the exhaust/emissions system and can have no effect on the engine. The real problem one could encounter is derating due to insufficient NOx conversion. But that could be dealt with by simply adding good DEF and running it for a while followed by five or six ignition cycles.

 

[Neal]

Always used truck stop DEF, will continue to use truck stop DEF. I have used boxed DEF on occasion, not sure why, maybe just to top off at a non truck stop fuel stop.