Taking the mystery out of DEF Heaters

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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. smile 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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I always thought heavy-duty diesels had heaters in the DEF tank or it's just a heater for the supply lines?
 

Snagglefoot

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Originally Posted by nthach
I always thought heavy-duty diesels had heaters in the DEF tank or it's just a heater for the supply lines?
Yes, the video shows the DEF tank with the heater. The guy is replacing the heater in it that crapped out. The DEF tank does not look like a windshield washer tank. It's mounted below the body like a mini-gas tank. I believe there is a new design for a 3.0 diesel with the tank under the hood.
 
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DEF has got to the most stupid thing ever introduced to the diesel world and is such a waste of time, money and effort. It has been proven it barely helps emissions and is such a costly, BS system to maintain and repair. Leave it up to the alphabet groups to implement something as ridiculous as injecting urine into exhaust to gain a .0000001% reduction in emissions. So glad I still have my 05 PSD with straight 4" exhaust, no CAT and no DPF.
 
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Originally Posted by racin4ds
DEF has got to the most stupid thing ever introduced to the diesel world and is such a waste of time, money and effort. It has been proven it barely helps emissions and is such a costly, BS system to maintain and repair. Leave it up to the alphabet groups to implement something as ridiculous as injecting urine into exhaust to gain a .0000001% reduction in emissions. So glad I still have my 05 PSD with straight 4" exhaust, no CAT and no DPF.
^^^ This is a completely made up statement. A DEF/SCR equipped diesel emits no nitrogen oxides. The only other way to reduce/eliminate NOx is to not run the engine. Science.
 
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I only had one DEF related issue on my 2017. Got the countdown one winter. Maybe only -15C and towing the horse trailer. Counted down a few km and then it cleared itself. I think the tank was 1/2, I topped it up once home and never another issue. I have cruised this thing in everything up to -40. No issues what so ever. I have also run the tank pretty much full in the cold. At 1/2 I like to toss in a 2.5gal jug, which pretty much fills her up. No issues in the extreme cold. The 3500 has its tank mounted ahead of the fuel tank. It has a skid plate and is level or above the frame rails.
 
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Originally Posted by BMWTurboDzl
The only other way to reduce/eliminate NOx is to not run the engine.
Or a heavy dose of EGR like what Navistar and CAT did, VW did as well before Bluetec and Dieselgate. CAT is no longer making on-road engines and Navistar is now pushing Cummins or relabeled MAN engines after the MaxxForce debacle. With SCR, why is EGR still being used?
 
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The GM 2.8 in the Canyon'Rado has EGR, SCR, and DPF. I doubt, however, frozen DEF caused today's issue... It died completely while I was driving. I posted about it in the other thread.
 
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Originally Posted by racin4ds
DEF has got to the most stupid thing ever introduced to the diesel world and is such a waste of time, money and effort. It has been proven it barely helps emissions and is such a costly, BS system to maintain and repair. Leave it up to the alphabet groups to implement something as ridiculous as injecting urine into exhaust to gain a .0000001% reduction in emissions. So glad I still have my 05 PSD with straight 4" exhaust, no CAT and no DPF.
I will play it: Who prove it? Sources?
 
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Originally Posted by BMWTurboDzl
Originally Posted by racin4ds
DEF has got to the most stupid thing ever introduced to the diesel world and is such a waste of time, money and effort. It has been proven it barely helps emissions and is such a costly, BS system to maintain and repair. Leave it up to the alphabet groups to implement something as ridiculous as injecting urine into exhaust to gain a .0000001% reduction in emissions. So glad I still have my 05 PSD with straight 4" exhaust, no CAT and no DPF.
^^^ This is a completely made up statement. A DEF/SCR equipped diesel emits no nitrogen oxides. The only other way to reduce/eliminate NOx is to not run the engine. Science.
Who needs science? Just rip off whatever emissions equipment you want to and then tune 'er up so she smokes real good!
 
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Originally Posted by nthach
Originally Posted by BMWTurboDzl
The only other way to reduce/eliminate NOx is to not run the engine.
Or a heavy dose of EGR like what Navistar and CAT did, VW did as well before Bluetec and Dieselgate. CAT is no longer making on-road engines and Navistar is now pushing Cummins or relabeled MAN engines after the MaxxForce debacle. With SCR, why is EGR still being used?
As I remember it CAT and Navistar could not reliably reduce the levels enough to meet emissions requirements without compromising reliability of the system itself. SCR is icing on the cake. As for why EGR with SCR? I suspect it's a combination of packaging and/or the maximum efficiency of the SCR catalyst itself. Rest assured if automakers could get rid of EGR they would. They'd save a ton of $$ on recalls and warranty repairs.
 
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Originally Posted by BMWTurboDzl
Rest assured if automakers could get rid of EGR they would. They'd save a ton of $$ on recalls and warranty repairs.
Pre xDI EGR was actually pretty reliable on gas engines - save for plugged passages on Honda engines and DPFE sensors on Fords - there was much less soot in the exhaust stream. I think someone here does an EGR delete on his fleet of PSDs for reliability reasons.
 
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