At What Temperature Does Def Freeze

At what temperature does DEF freeze? Can it actually freeze if you leave a vehicle out in the cold during the winter? Can a truck still function with frozen DEF, or do you need to do something to warm it up first?

As far as I know, your truck will start with frozen DEF just fine. It will probably freeze once the temperature drops below 13°F, but most heating systems are set up to thaw it quickly. I live up north where it gets frigid, but it's been a while since I read any manuals, so I could be wrong.

You don't need to thaw def. But yes it will freeze around 12 degrees farenheit.