Best DEF gauge for checking purity

[wagonmaster2]

I've been reading a lot about using a DEF gauge to be sure it meets the correct purity.
Is there any perticular model or style that most RVers prefer? And if the tank is less than full how is it possible to reach the fluid level for checking the tank?

[Lt Dan]

This is the one I use. Just a drop on the lens and hold it up to the light and it will display the DEF concentration. If the tank is low, you would have to pull some out with a vinyl tube.
https://www.amazon.com/gp/product/B073Q2LSG9

[Gary RVRoamer]

Is fake DEF really a problem? Are you buying unlabeled jugs from some DIY chemist? Otherwise, commercially available DEF will near-always have the API certification mark on the container, showing that it meets the API DEF standard (AUS 32).



If in doubt because of long storage or exposure to other chemicals, a simple eyeball check will usually identify any contamination - as long as it remains clear you can be pretty sure its is still ok.

[Wayne M]

Before I pay for a container of DEF I remove the cap to see if the pull off tab is still intact. If not I go to the next jug. Never have had a problem with DEF in my MH.

[wagonmaster2]

Guess maybe it just isn't the problem I have read about. Usually buy mine at Wal Mart but haven't learned how to read the date on the jug yet, but do always remove the cap to check the seal on the spout. Never know how long the jug may have set on the shelf or in storage someplace.

[Cousin Ed]

Does anybody realy think someone is going to go to all the work of carrying 25 pound jugs home and then filling then with water and bringing them back to save $10. I was a cop too long to think a dirtbag would make that effort!

[hypoxia]

I wonder why I would get jugs of DEF instead of filling at the truck stop? Loves nearby is $4.35/gallon and Walmart is $4.72 including sales tax.

[Country Road]

Originally Posted by Gary RVRoamer

Is fake DEF really a problem? Are you buying unlabeled jugs from some DIY chemist? Otherwise, commercially available DEF will near-always have the API certification mark on the container, showing that it meets the API DEF standard (AUS 32).



If in doubt because of long storage or exposure to other chemicals, a simple eyeball check will usually identify any contamination - as long as it remains clear you can be pretty sure its is still ok.

My sentiments totally. Those who worry about def need to move on to the next problem. But I do understand the OP’s concern because that’s just the way it is.

[mlpeloquin]

In the beginning people would remove the DEF, fill with water and return for a refund. Walmart was not smart enough to check to see if the seal was broken. Many had to have expensive repairs do to not checking the DEF. I have not heard of any problems in the past couple of years. It doesn't take long to test just to make sure. Loves, and others are not close to many people in cities. So a jug at Walmart will get you there. Some places we go do not have Flying "J's", Loves, etc.. But when there is one, we fill up there.

[153stars]

Newer refractometers have gauge/scale for DEF . But it would really just be specific gravity/freeze point not contamination.