Def fluid in 2015 PSD & winter

[Donald]

I have not be able to figure out if there is a DEF fluid heater that runs when the truck is off. DEF can freeze so what happens overnight when it's 10F outside? I know the manual it says not to add DEF fluid in the winter and then shut-off the truck. The DEF fluid pump at the truck stop has a quilted blanket all around the pump with a flap you can open to remove the nozzle. So people obviously work about it freezing. I would think the vehicle battery would discharge in a few days in the winter if battery power was used to run the DEF fluid heater when the truck is off.

 

[P10crew]

Donald when my 2015 psd was brand new it threw a code that when ford checked it out def heater failure. They were on national back order. I just drove it and am still driving it with supposedly no def heater. Winters are brutal at times here and no problems so far with def @110,000 miles . Everything else has happened to the drive train of this joke but not def related.

 

[roadrunner1]

No DEF heat when truck isn't running. My ‘15 is currently at 125,000 mi., trouble-free.

 

[themaxx]

Can't comment on the Ford system specifically, but the DEF systems I've seen on equipment have some sort of heating system that operates when the equipment or truck is running. It may be electric or engine coolant heated. Keep in mind that the DEF is an aftertreatment. The engine does not need it to run. Yes the DPF will get dirtier faster without it, but the short time between startup and DEF thaw shouldn't contribute to that much. Someone check me if I'm wrong here.

 

[BMWTurboDzl]

Originally Posted by themaxx

Can't comment on the Ford system specifically, but the DEF systems I've seen on equipment have some sort of heating system that operates when the equipment or truck is running. It may be electric or engine coolant heated. Keep in mind that the DEF is an aftertreatment. The engine does not need it to run. Yes the DPF will get dirtier faster without it, but the short time between startup and DEF thaw shouldn't contribute to that much. Someone check me if I'm wrong here.

You're basically correct in that they're all designed to warm the DEF in some way. I can't think of how it would impact DPF loading since it's upstream of the SCR (DEF Injection). EGR -.> DPF ->> SCR--> Tailpipe.

 

[Chris142]

It may circulate it through a heat exchanger.

 

[roadrunner1]

Ford uses an electric heater within the DEF tank on the 6,7

 

[edyvw]

No heat if it is not running. Now, in heavier equipment there are coolant lines too, so they postpone coolng off of DEF. Not sure whether heavy equipment has heater that runs when needed if engine off. Electric heater in tank is known issue in early SCR systems as most vehicle manufacturers were using BOSCH supplied heater. DEF is good to 12f, and 10f outside should not create too much of an issue. However, droppoing further might. But as someone mentioned, engine does not need DEF to run, and manufacturers took that into consideration. ON BMW X5 35d I had there were two DEF tanks. One, so called active had DEF heater and stored 1.6 gallons of DEF, second was passive tanks storing 5.4 gallons of DEF, but no heater. I drove and park car as low as -37f, never had issue due to cold temperature. Heating unit on other hand was problematic and failed once during summer.

 

[BBDartCA]

There are a variety of strategies to manage DEF freezing. Firstly, from a regulatory standpoint, the vehicle must inhibit operation (obviously usually starting), if DEF is frozen (there are a variety of ways to monitor this). The methods of maintaining DEF temperatures include a combination of heated Def lines, heating tanks electrically or with engine coolant. Plus there is (under interpretation) some allowance for startup without DEF system fully fault checked. https://www.govinfo.gov/content/pkg/FR-2014-08-08/pdf/2014-18738.pdf#page=17

 

[Skippy722]

My buddies DEF froze on him over night, and it started a countdown in miles till he was limited to 5mph. Ended up causing a fairly significant amount of damage. It was -5F out though.

 

[P10crew]

Skippy I've been in -35 with no problems. Who even knows if my heater is working or not? Our F dealer here is the biggest bunch of bozos I've ever seen. I know for a fact that the service manager that I have been forced to talk to on several occasions was convicted of embezzlement at his previous job. There is NO hope here. Junk!