Plugging your truck in is a coolant heater or block heater, that is all it does.

Yes the DEF freezes solid. Many thousands if not 100s of thousands of trucks driving around in subzero climates. It seems reasonable that the engineers from all these different manufacturers thought about the fact that the def freezes huh?? There are heaters that thaw the DEF. It knows that it can’t use DEF until it’s thawed. Drive it, don’t worry about it, many, many thousands of these trucks driving around without a single worry given to the DEF freezing and they work great.

 

As you are driving the truck, the diesel exhaust fluid thaws. Yes it does freeze solid when parked as there is no heater that heats it while the truck is not running. The fluid drains back into the tank when not in use. The heater keeps the lines and tank thawed while the truck is running. I personally have not had any issues with my truck at -25.

 

The lines are purged every time you shut the truck off so nothing in them to freeze.

 

Good information.

 

If I remember correctly I think to meet emissions requirements the truck has 1 hour to thaw and begin injecting DEF.

 

Thanks for all the replies. Like I said these where shower thoughts. lol

Maybe its me reading to many of these threads and over thinking things.

 

Thanks for all the replies. Like I said these where shower thoughts. lol

Maybe its me reading to many of these threads and over thinking things.

Sounds like you might be.

I don't know how long the time interval is, but the programming recognizes 'frozen tank status' and does whatever it does so the truck can be used.

I'm not in a -40 area, but we get lots of nights when its' cold enough to freeze def and usually a week or so when the daytime temps aren't warm enough to thaw def.

Anyway, my LML and L5P trucks lived outside and got started/used every morning. (without block heater)
Never had any cold related issue.
(LM2 lives outside too, but I don't head out every morning like I did when I ran the LML and L5P)

Do make sure you have the 'elevated idle' enabled in the settings.
It will greatly reduce the warmup time for both the engine and transmission.

 

Old thread, I know, but I may be experiencing this now (Frozen DEF tank that can’t thaw). I’m definitely not using def and the truck stopped regennin. On a road trip north of Fairbanks and just sleeping in the truck the last 3 days (Hasn’t been shut off since I left). Anyway, the warmest I’ve seen is -8F and down to -44F. Next few days the high for the day is -30+. Even with the engine running and driving significant distances, that DEF is gonna freeze and the truck isn’t able to liquify it for use. I got a CEL 12 hours ago or so.. I’m kind of interested to see how this turns out.

 

I doubt your going to see much more as that thread was from 2 years ago....

 

-7° never plugged truck in on my way to the doctor truck stalled and will not start if I plug it in will that help???

 

Nope.
You might have gelled fuel, and block heater doesn't fix that.

Out of curiosity, what year and engine do you have (since it's not in avatar or signature)?

Also, how long did it get warmed up before heading out?
Also, are you in an area that typically gets that cold during winter, and was the fuel in it purchased in that location and during winter?