This is a topic that a goodly amount of people don't care about but some do. A DEF Heater. DEF is used in many modern diesel engines as part of their pollution control system. We just had a posting on a couple of folks trying to drive to Alaska. Although their codes might not have confirmed this, they were parked overnight in Fort St. John in temps approaching -40 F at night. DEF freezes at +12 F.
Here is a video (really bad sound), that shows a guy replacing a DEF heater in a Duramax. It is OK to freeze and thaw DEF, but to be honest, if its -40 F and the truck has been sitting overnight it will take quite a while for the DEF heater to thaw it out. Notice in this model, the DEF tank is not under the hood. It's just sitting beneath the vehicle. There is no insulation on the tank. It does not have plug in heater unless you do something special. I suppose installing a oil pan heater beneath it would work. Some people are asking how is it all the other Duramax vehicles are driving around just fine at -30 C. It's because Fort St. John is an oil patch town and most of these guys have their truck inside their two car or three car garage at night.
Anyhow, enjoy and please correct anything you see wrong. I'm no expert on this.
https://www.youtube.com/watch?v=pXSSbrZyrLc
Here is a video (really bad sound), that shows a guy replacing a DEF heater in a Duramax. It is OK to freeze and thaw DEF, but to be honest, if its -40 F and the truck has been sitting overnight it will take quite a while for the DEF heater to thaw it out. Notice in this model, the DEF tank is not under the hood. It's just sitting beneath the vehicle. There is no insulation on the tank. It does not have plug in heater unless you do something special. I suppose installing a oil pan heater beneath it would work. Some people are asking how is it all the other Duramax vehicles are driving around just fine at -30 C. It's because Fort St. John is an oil patch town and most of these guys have their truck inside their two car or three car garage at night.
Anyhow, enjoy and please correct anything you see wrong. I'm no expert on this.
https://www.youtube.com/watch?v=pXSSbrZyrLc
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