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Hello all my names Jess im new to the site and had a question. Im not trolling or trying to start a fight, but figured there may be a lot of people smarter than me that can answer this question for me or change my opinion lol. My question is how can the EPA really believe that a
DPF is good for the environment? I drive a diesel truck have for years, so has most of my family. My current truck is a 2011 F350 with a 6.7 powerstroke diesel Im currently getting 17.1 mpg. Now for a truck this size that is not bad but through most of my research if i were to remove the dpf i would be over 20mpg easy. My dad had a 2009 F350 with the 6.4L when he first got it it got 13 MPG he did do the dpf delete and went to 23 MPG. Now that is a huge improvement. I guess my logic is how is burning that much more fossil fuel better for the environment? The dpf is mainly to stop black smoke (soot) but has to have a regeneration cycle to clean the filter which burns out the the soot. My argument in my head i guess is if i start a fire the more fuel i burn the more smoke or pollution i make. So without a dpf couldnt our auto manufactures be able to push these trucks up to 30 mpg or more for us normal drivers? I know the founder of this site got 30 mpg in a truck just like mine but what could he do in one i can get 25 or 30 mpg. in my opinion the less fuel burned the less pollution and the lower your carbon footprint. Rant over Lol thanks for any response

Welcome to the forum! Nice to see another full size diesel truck guy here!

Sorry tho, mine is an 07 pre dpf.

The DPF is not for the environment, but for people's lungs in a crowded city. The catalytic converter is to reduce the NOx emissions that form smog, also for crowded cities.. I guess the EPA assumes everyone lives in NYC. I dont think diesels emit much carbon monoxides anyways.

You could probably chip your truck and disable the DPF if you wanted to, I dont think it will clog up if it does not regenerate. We also have members that do water injection with great improvements in economy.

The DPF will clog up in short order if it can't regenerate. Particulates are bad for people's lungs. It's a tradeoff, more CO2 but less particulates. The EPA seems to have decided it's worth the tradeoff in this case. We're also only very early into implementing DPFs and learning how best to do it. Much like when catalytic converters came out, the hit was pretty big at first but manufacturers got better with them over time. The same will happen with DPFs.

I dont think diesels emit much carbon monoxides anyways.

Correct. Gasoline vehicles emit more CO, or at least in the EU CO limits are higher.

For the OP, DPFs are there because particulates increase the risk of respiratory diseases and cancer. Please don't remove the filter.

Euro 6 requirements (come into force in 2014, but manufacturers are ready in advance) are tougher and are close to US standards. As a result we should see engineering improvements that can be applied globally both to improve the fuel efficiency of the filters and to improve diesel engines to reduce particulates in the first place, but those will take time to move through the fleet.

Welcome
17mpg>20 mpg at 60 mph 3.5GPH VS 3.0 GPH-
It is plausible that a DPF would use .5gph(pure guess but seems OK)

13mpg>23 mpg 4.6gph vs 2.6gph
Wow-I wouldn't guess a DPF would waste 2gph??
Does anyone here actually know how much fuel the DPF wastes??
Sure hope it isn't 2gph

On the other hand the most current Ford TD gets better mpg than ANY previous full sized pickup TD. Much better than the 2004 6.0 Ford or the pre DPF Duramax

I can't picture it actually using 1/2 gph-seems too high- considering the mpg Xcel got with it.
Pretty sure he got 25mpg at 60 mph-just 2.4gph-
if it wasted .5gph deleting the DPF would put it at 31.5mpg 60 mph- no way a 7500 lb brick like that can get over 30 mpg with a 6.7 liter V-8.

You really have no choice-gotten leave it on
My suspicion is removing it would not improve mpg by more than 1-1.5.
Charlie
PS I wonder why they just can't electrically heat the DPF filter(I assume it is ceramic or maybe steel)- maybe while blasting it with EXTREMELY lean CC gases(plenty of O2)
Must be some very good reason they have to waste fuel to burn these particles.They must have tried the obvious-electrically heating etc

Think heating with fuel is the way to go. Pretty much everything in the fuel is converted to heat if it's just burnt there in the DPF. Compared to maybe 15% efficiency after conversion losses for fuel -> engine rotation -> alternator generation -> heat.

seftonm
Probably right
But heat the mesh(it is some sort of mechanical filter right) would put the heat right on the particles.They don't do it that way-so obviously it didn't/wouldn't work as well.
Too bad they can't mechanically "scrape" or shake the filter-catch the particles
Oh well
Must not be wasting too much fuel- not getting 25 mpg 60 mph

Thanks for all the welcomes guys, Ive read through all your posts and I understand the dpf is suppossed to filter out particulates and understand that the regeneration is cleaning the filter but in cleaning the filter it is blowing the particles out of the filter. Does anyone know if the trucks were epa tested during regeneration? Cause in my mind if its cleaning the exaust filter out it is blowing out what it caught. By the way I dont believe i would gain as much deleting the dpf on the 6.7 as my dad did on his 6.4. Ive done some research and apparrently the 6.4 injected diesel into the dpf through all eight injectors and the 6.7 only use the 4 on the left bank that seems as if it would use a lil less fuel for dpf burn off. But I can say that the egt during regen i have seen around 1500 degrees and dpf burnoff lasts anywhere from 10 to 15 minutes that ive noticed I average a regen about every 150 miles or so, approximately 2 per tank. It seems as if every time I hit the 20 mpg mark on my avg mpg it goes into regen and drops down to 18 lol. My instant gauge is approx 1 mpg high though. Im pretty happy with my milage although im no hypermiler but i have gotten decent mileage so far. I totally believe if someone who gets over 100 mpg in a car could make these trucks get 25 - 30 mpg but i also believe he could have gotten better without the dpf. I believe i read of a guy on here with a older duramax who got around 30mpg.

Hi,

Here in France, 15000 people per year are killed by particle pollution. These particles are coming 50% from diesel and 50% from house heating (fuel and wood).

DPF permit to filter out the biggest particles.
Sadly most of these big particles are already filtered out by our natural protections (hairs in the nose...), while the thin particles are going down deeply into the lungs where they are generating all sort of health problems.
Also the DPF are generating NOx when they are in a regeneration cycle. New generation DPF are using lower temperatures so are generating much fewer NOx, but they need special products that have to be refilled at each oil change.

Yes the DPF makes you consume more and so generate more CO2, but particles are killing people and make others sick today, while CO2 will p*ss us all off during the next 50 years.

Despite what I'm saying that seams rather negative, please keep your DPF. I don't think you want to leave in smog (http://en.wikipedia.org/wiki/Smog).

I changed my old Euro II 1997 diesel for a old 2006 Prius (see my sig) because this later is generating 20 times fewer pollutants than the former. I'm learning the Prius to try to lower my consumption with it, but I know it will always cost me more per km because gasoline is 10% more expensive in France than diesel.
I could have asked to destroy my old diesel, but I'm selling it to a student that need a cheap car that will not cost a lot. Ecology is also about helping other people.

Have fun,

Denis.

I've averaged 30+ on my dmax on one 200 mile trop

Tuned, intake, exhaust, LRR michelins at 80 psi, covered bed, 60 ish mph, spraying water/meth (straight water on that trip)


The water meth is supposed to help dpf equipped trucks burn cleaner and regen less. There's been a few articles in diesel power mag, or diesel world mag, can't remember which.

Why do diesels produce hydrocarbon particles
You would think that the really O2 rich combustion would burn the fuel very completely

Too bad there isn't some way to preferentially separate out the particles in the exhaust stream and send them back thru the combustion chamber-
Perhaps centrifuge them out using the turbine-recycle them thru the combustion chamber
Yeah-too complicated

It does seem to be a really crude solution-wasting fuel to get them hot enough to burn-
producing more CO2-poorer mpg
Simple solution- but crude--must really gall the engineers to have to use this sort of system
They must be working on a more elegant solution

From an overall perspective diesels are lean burning. But since the combustion process starts basically as soon as the fuel is injected, the mixture in the combustion chamber is not uniform and there are areas that can be locally rich even though the average over the entire combustion chamber is still lean.

bocephus1983, the filter is cleaned out by incinerating the particles. That's why the DPF needs to be heated during regen. This then accumulates as ash in the DPF and it has to be emptied at some point. The ash does not get nearly as airborne as the soot would and is a lot less dangerous to a person's lungs.

Too bad there isn't some way to preferentially separate out the particles in the exhaust stream and send them back thru the combustion chamber-
Perhaps centrifuge them out using the turbine-recycle them thru the combustion chamber
Yeah-too complicated

Isn't it what EGR are doing ? all the exhaust being sent back.

Have fun,

Denis.

I don't think it would Send ALL the exhaust back??
If you did that eventually you would have no O2

Just seems so wasteful= but apparently there isn't any better way now

EGR sends a portion of the exhaust back. It's for reducing combustion chamber temperatures and NOx. Reducing combustion chamber temperature actually increases particulates I believe.

Does anyone know how much fuel is wasted by the new Ford TD - per hour-at a steady 60 mph?

Check a recent review that Wayne did on a diesel, Silverado I believe.. it was not too bad but it probably depends on your load and how often it has to regen... a calculated 2mpg hit seems to stick in my mind.

Roughly 10% ?? Figure .3 gph ??
Not too bad

I've averaged 30+ on my dmax on one 200 mile trop

Tuned, intake, exhaust, LRR michelins at 80 psi, covered bed, 60 ish mph, spraying water/meth (straight water on that trip)


The water meth is supposed to help dpf equipped trucks burn cleaner and regen less. There's been a few articles in diesel power mag, or diesel world mag, can't remember which.

I would like to check in to this water Meth injection but what exactly does this do inject into the exhaust I assume for cooler egt? I'm learning quite a bit here about how the DPF is supposed to work and to seems like its just a first effort to clean up exhaust hopefully they can keep advancing the systems. I was able to get 25.3 MPG out of my truck on a 75 mile run today without a regen I'm pretty stoked about that and wish I didn't have to worry about them but that's not gonna happen. I wonder if they could ad some other kind of fluid to clean out the filters? I know we already have urea but couldn't there be something that just cleans out the filter more efficiently?

I think it goes into the intake.. it probably allows less EGR and more boost without the exhaust temperatures melting your valves.

Only thing I know about diesels.. higher compression = higher efficiency

Yup. Sprays into intake.

I think I read somewhere that in WW2 the Germans sprayed water methanol into one of their supercharged fighters??
Maybe they even used Nitrous Oxide boost in a fighter.
Seems like they even had a Diesel engine airplane- a multiengine plane-maybe some sort of long range recon/bomber that was supposed to loiter over the Atlantic sinking shipping??

Krauts were pretty clever-good thing they over reached