I have an appointment in a few days to get the DEF heater replaced in my 2012 F350. I'm wondering if I should be concerned about driving it this weekend when the low temps are in the single digits? Will it just go into limp mode if the fluid freezes or will there be more damage done?

 

no more damage. Probably have the code pop up. Really don't know if it would force you to go into limp mode.