[ToolmanJohn]

Anyone used one for checking the actual 32.5% Urea concentration of their DEF before using it?

I've seen them for sale on Amazon, and wondering how bad could some old DEF container be if it was on the shelf and not rotated out before purchasing?

Should I just trust the "use by" date on the jug if it has one? Typically I use about 5 gallons (2 X 2.5 gallon jugs) a year. I store them in my basement (55-65°F year round).

 

[fincher]

I would just purchase when needed. This will ensure you will have fairly fresh urea. I buy from dealer..stuff is cheap. Or, you can buy a small amount to keep on-hand.