Rancher Will wrote:
...
When a DEF equiped truck is parked over night, does the truck have a built in heater from the battery, or external power source, to keep the DEF from chiling below freezing point? If it is a battery power source, how long can a truck be parked with the engine not running without running the battery down keeping the DEF above freezing? My semi trucks often park over night at temperatures far below Zero. And, often park over a weekend and/or more when the driver is required to take his DOT required break.
I am interested in others experience since I may be required to buy DEF equiped trucks in the future.
the DEF heater is only on when the vehicle is on. apparently it takes a while to get all the components up to temp where DEF injection works.
according to the Ford diesel supplement doc provided to the owner, it says
DEF will freeze below 12°F (-11°C); however, your vehicle is equipped
with an automatic preheating system which allows the DEF system to
operate below 12°F (-11°C). When the vehicle is not in operation for an extended period of time with temperatures at or below 12°F (-11°C), the DEF tank could freeze. If the tank is OVERFILLED and freezes, it could be damaged, therefore DO NOT OVERFILL.
