is DEF fluid flammable?

Urea ammonia whatever. It's 30% piss.

Here is a good question: If I'm out of DEF can I pee in the DEF tank to get to the closest truck stop?

 

How much can you pee?
Better be a gallon or so.

Might want to add a little water to the mix to get it right?

 

Def is fertilizer... It is a 32-0-0 uan solution. And it is most definetally IS corrosive, but only mildly so... You can safely put you hands in it with little to no effects. Now if you left your hands in it for a couple days you might have some bad things begin to occurs. Yes you can make your own by mixing granular urea (46-0-0) with hot distilled water. The problem lies in that when uan solutions reach 21% the solution is fully saturated (meaning that even if you disolve more urea into it, the balance over 21% will not stay in solution, it will crystalize and "fall out" of solution). There are obviously ways to over come this... But they are not easily done in ones back yard. I know all this because I used to work for a fertilizer company, and made liquid fertilizer in 40,000 batches. I have made 21-0-0, 21-0-06, 0-0-13, and several others. Urea is essentially granular ammonia... So def is a weak ammonia solution... Ammonia is corrosive... So DEF is a weak corrosive.

 

There is a chemical reaction between urea and water when they mix that causes the water to cool very rapidly... That why you had to go slow. I once had to make a small batch of 21-0-06 when my boiler was not working... Water was 70 degrees when I started, once I dumped the urea in the water temp dropped to below freezing in a matter of minutes, and turned to slush... It even made frost on the outside of the mixer tank, and stalled the circulation pump. That small batch took 10 times longer than a normal size batch did with 180 degree water.

 

Somebody is educated in DEF. I'll give you a mild corrosive. To hear everyone else tell it they think it melts steel like butter.