DEF Fluid Brand Preference

[Gearclash]

3 hours ago, Farmall 1466 said:

Do SCR systems not have a DPF? Than sooth emissions would be way too high to pass emissions tests right?

And EGR/DPF systems do make use of SCR too right? Virtually all new tractors consume AdBlue I think and otherwise NOx emissions would be too high?

So what is the difference?

SCR (Selective Catalytic Reduction) is to reduce the emissions of NOx.  DEF (or AdBlue to you) is used to this end.  EGR ([cooled] Exhaust Gas Recirculation) accomplishes the same thing, but I see EGR as being a much poorer choice overall due the negative effects on the engine.

DPF (Diesel Particulate Filter) is there to remove the particulate emissions (soot) from the exhaust.  

The nature of diesel combustion is such that if the engine is tuned to reduce particulates, NOx goes up and vice versa.  CNH apparently has chosen to go the route of tuning their diesels for a minimum of particulate emission, which means they hardly need a DPF, but have a relatively high use of DEF.

It is perfectly possible for a diesel to have both a DPF, and use SCR.  Each is intended to control a different pollutant.

[SDman]

3 hours ago, Farmall 1466 said:

Do SCR systems not have a DPF? Than sooth emissions would be way too high to pass emissions tests right?

And EGR/DPF systems do make use of SCR too right? Virtually all new tractors consume AdBlue I think and otherwise NOx emissions would be too high?

So what is the difference?

Different engine manufacturers have/had different approaches to meeting modern emissions regulations.

CaseIH/New Holland/CNH/FPT(Fiat Power Trains) engines over 100HP achieve emissions regulations by SCR only. No DPF or EGR is used. They do this by running an engine that operates at roughly late 1990s/early 2000s emissions regulations....and then treat the higher Nox emissions by SCR/DEF/AdBlue only. The bad thing about this setup is that they use more DEF than most engine manufacturers. The good thing is the engine is just a powerplant with no actual emissions equipment on it. The engine runs a lot cleaner in terms of oil dilution this way, and there is no regeneration needed for a DPF filter.

Most other engine manufacturers use cooled EGR with a DPF filter...and some do use an SCR system in addition. With cooled EGR, the NOx is lower due to cooler combustion temperatures....so less DEF is needed(with early Tier IV emissions, some engine companies didn't need any DEF). The drawback to this is that the DPF will eventually plug up with soot due to the lower combustion temperatures....forcing a regeneration, which is spraying raw diesel fuel into the exhaust to raise exhaust temperatures to burn the soot out of the DPF. Also, the engine will have an EGR cooler system of some sort to cool some of the exhaust for the lower combustion temperatures. Also, the engine oil gets dirtier this way with all the exhaust gas being recirculated in the engine.

So, there are some engines that are SCR-only, some are DPF/cooled EGR only, and some that run a combination of both systems.

[U-C]

1 hour ago, SDman said:

Different engine manufacturers have/had different approaches to meeting modern emissions regulations.

CaseIH/New Holland/CNH/FPT(Fiat Power Trains) engines over 100HP achieve emissions regulations by SCR only. No DPF or EGR is used. They do this by running an engine that operates at roughly late 1990s/early 2000s emissions regulations....and then treat the higher Nox emissions by SCR/DEF/AdBlue only. The bad thing about this setup is that they use more DEF than most engine manufacturers. The good thing is the engine is just a powerplant with no actual emissions equipment on it. The engine runs a lot cleaner in terms of oil dilution this way, and there is no regeneration needed for a DPF filter.

Most other engine manufacturers use cooled EGR with a DPF filter...and some do use an SCR system in addition. With cooled EGR, the NOx is lower due to cooler combustion temperatures....so less DEF is needed(with early Tier IV emissions, some engine companies didn't need any DEF). The drawback to this is that the DPF will eventually plug up with soot due to the lower combustion temperatures....forcing a regeneration, which is spraying raw diesel fuel into the exhaust to raise exhaust temperatures to burn the soot out of the DPF. Also, the engine will have an EGR cooler system of some sort to cool some of the exhaust for the lower combustion temperatures. Also, the engine oil gets dirtier this way with all the exhaust gas being recirculated in the engine.

So, there are some engines that are SCR-only, some are DPF/cooled EGR only, and some that run a combination of both systems.

CNH/FPT's engine research and developement center is in Arbon Switzerland in the Former Diesel engine RND shop of the Swiss SAURER truck company. 

[1965Dennis]

I just looked at Tractor Supply and they have BlueDef at $23.99 for 2-1/2 gallon and Shell for $15.99.

Dealer filled the DEF tank and fuel tank when I bought it. Should be a while before I need to buy some.

[Farmall 1466]

9 hours ago, SDman said:

So, there are some engines that are SCR-only, some are DPF/cooled EGR only, and some that run a combination of both systems.

Basically all new diesel cars on this side of the ocean use SCR, DPF and EGR. I always wondered why they would use SCR AND EGR at the same time, as the purpose is the same. Well anyways, by doing both, Mercedes has developed a car diesel with 0 milligrams of NOx emissions per kilometer, according to a test of a German car magazine (in a test on the road, not in laboratory circumstances). A masterpiece of engineering if you ask me. I'm still amazed why diesels are so hated upon in Europe. The time of stinky, smoky diesels is long behind us. Lower CO2 emissions, ultra low NOx emissions for more and more diesels, less emissions of ultra small particulate matter (direct injected gasoline cars emit shocking amounts of this). Sad, because in 13 years time, we will all be forced into an EV here

[TeachersPet1066]

9 hours ago, 1965Dennis said:

I just looked at Tractor Supply and they have BlueDef at $23.99 for 2-1/2 gallon and Shell for $15.99.

Curious as soon as I saw this post.  Son & I took dad to get pig feed Saturday and DEF was threatening to go into limp mode in 50 miles.  He said that he just added 2.5 gallons when it did it last weekend…but it must have been empty.

[New Englander]

2 hours ago, Farmall 1466 said:

Basically all new diesel cars on this side of the ocean use SCR, DPF and EGR. I always wondered why they would use SCR AND EGR at the same time, as the purpose is the same. Well anyways, by doing both, Mercedes has developed a car diesel with 0 milligrams of NOx emissions per kilometer, according to a test of a German car magazine (in a test on the road, not in laboratory circumstances). A masterpiece of engineering if you ask me. I'm still amazed why diesels are so hated upon in Europe. The time of stinky, smoky diesels is long behind us. Lower CO2 emissions, ultra low NOx emissions for more and more diesels, less emissions of ultra small particulate matter (direct injected gasoline cars emit shocking amounts of this). Sad, because in 13 years time, we will all be forced into an EV here

Mercedes got caught up in a cheating scandal just like VW discovered after someone dropped a dime on VW. Is the engine you refer to post scandal?

The settlement addresses allegations made in separate civil complaints filed by the United States and CARB today in the District of Columbia that, from 2009 to 2016, Daimler manufactured, imported, and sold more than 250,000 diesel Sprinter vans and passenger cars with undisclosed AECDs and defeat devices programmed into the vehicles’ complex emissions control software.  These devices cause the vehicles to produce compliant results during emissions testing.  But when not running a test, the vehicles’ emissions controls perform differently, and less effectively, resulting in an increase in NOx emissions above compliant levels. 

[Farmall 1466]

2 hours ago, New Englander said:

Mercedes got caught up in a cheating scandal just like VW discovered after someone dropped a dime on VW. Is the engine you refer to post scandal?

No, no. That was not so smart from them Germans. The engine I'm talking about was quite a new design in the test, I think the test was from late 2019. And it was a test in practise, so the cheating wouldn't have worked anyways. Thats how VW got caught basically. Practise test results were miles off from lab cirucumstances tests.

[iowaboy1965]

7 hours ago, Farmall 1466 said:

, because in 13 years time, we will all be forced into an EV here

Only if we allow it. 

[Farmall 1466]

41 minutes ago, iowaboy1965 said:

Only if we allow it. 

Its not like we have too much to say in this. The EU is quite an undemocratic organisation actually. The people in the Commission, where most of the very important plans are made up, are not elected by the citizens of the EU. Then elected representatives have to vote about these plans.

[iowaboy1965]

19 minutes ago, Farmall 1466 said:

Its not like we have too much to say in this. The EU is quite an undemocratic organisation actually. The people in the Commission, where most of the very important plans are made up, are not elected by the citizens of the EU. Then elected representatives have to vote about these plans.

Right now we probably wouldn't buck them but I'm hopeful in another couple years we might ditch some of these questionable deals. Who knows. 🤷‍♂️

[Ihfan4life]

On 10/25/2022 at 8:06 AM, SDman said:

Diesel engines that run DEF/SCR-only emissions systems generally do not run any regeneration. Current CNH/FPT engines are this way. Diesels that use EGR/DPF emissions systems use regeneration. 

Say what?

 I was parked for over an hour for a “regene “ or burn off. 
Truck uses D.E.F…

 

[SDman]

28 minutes ago, Ihfan4life said:

Say what?

 I was parked for over an hour for a “regene “ or burn off. 
Truck uses D.E.F…

 

The regeneration was to clean the DPF/particulate filter, not the SCR chamber(which is what the DEF works with to reduce NOx). My service truck has a 6.7 PowerStroke that runs an EGR/DPF system in addition to using DEF as well. It regens as well, but not because of the DEF system. It's to clean out the DPF when it gets plugged with soot. 

[russ_alabama]

I asked the lady service manager at Dodge about who screws up the most on DEF DPF issues and what should I avoid (this was in '14, when I bought my ton cab/chassis Dodge).  She said that hot shot truck drivers experience the most issues, and to stay away from DEF at the pump.  She said (and I don't have the chemistry knowledge to promote what she said) that DEF does have a expiration date, and after that it doesn't combine well with NOS to turn most of it into some other thing, molecule wise.  The DEF tanks at the truck stop will have the old with the new thrown on top, and then it dilutes it's effectiveness.  I told her my plans of not driving the truck that many miles, as its a farm truck.  She said that folks that empty a DEF tank quickly ought to fill them up and run them out... but that in my case, I shouldn't leave a full DEF tank for a year at a time.  I'd promote deleting, but, then, it could go national inspection at some point and you need to keep all the old parts to go back.  But, how things are at this point, I'd promote deleting.