I might have been unclear in my statement. Ford has done a great job with the entire 6.7 truck package. Like you, I like my warranty. I would be at the front of the line defending Ford for canceling the warranty on a tuner equipped/programmed truck. My "Ford approved power to beat up on the Duramax" remark was a playful poke at Paul and his team.

Regards

 

The big question for those of us who don't salivate over tuners is one that 6.4 owners really do have to lose sleep over though.

The 6.4 I had was great, if and when the DPF would have been required to be replaced, the question is, spend $3K on a new one or spend $3K on a delete kit/tuner? I think I would have put a tuner on at that point. Out of warranty and moving on would have been my thinking.

I know that we are focused on the 6.7 but in 3 years or so, the same decision will rear its head. As great as the '11 trucks are right now, it's hard to say what will be going on in 2 to 4 years from now regarding DPF and tuners.

The only real issue is the legality of using an "off-road use only" product on the streets and being illegal as a result.

 

One of Navistar's biggest gripes about the SCR system is when its not functioning correctly the new engines of 2010 are actually emitting more Nox then the pre 2000 motors. The reason being that there are systems in place to catch the extra nox, so why worry what the engine is producing as long as we clean it up before it leaves the tailpipe. Can you comment on the truth of this statement or is it some more Navistar BS trying to cover their bad decision? Did the 6.7 team ever think about the "extreme egr" instead of the scr route?

 

I did a lot of reading on the Navistar site awhile ago about their strategy for EPA 2010 emissions.

They contend that their system is simpler than one equipped with SCR. To illustrate this they used to show off a truck they had equipped with an SCR system, and painted all the SCR parts yellow to demonstrate how much stuff is necessary for this system.

They also like to sell on the fact that their system requires no maintenance, as opposed to having to fill a DEF tank. I saw a long video that touted their belief that the burden for meeting the 2010 emissions compliance should rest with the engine builder, not the customer. They worked to minimize the perception of decreased fuel economy and constantly brought up the fact that theirs doesn't require filling a tank.

I don't know how well their systems compare in heavy duty trucks, but from what I've seen comparing the Ram/Cummins huge EGR system and that of the Ford and Chevy, I'm confident in the superiority of the SCR system. This stuff is simply not enough of an issue to offset the large fuel economy penalty paid by large EGR systems.

I wish I could find those videos, I'll do some searching later today when I get the chance.

 

There is a good video I'll have to find where Navistar does test on the DD15 and a Paccar motor to show that they will still run normal without def, or just by putting water in the system. I think the fact that Cummins abandoned their eegr program for the scr is proof in itself which is superior.

 

Also like to add that Caterpillar ditched their on road engine program because of problems with their C15 and egr. Caterpillar told these customers to pound sand when they bowed out. Actually they sold their crappy technology to Navistar.

 

I agree with you Tom... Also Navistar's touting leaves out one minor detail, in that how much more fuel there approach burns and that minor detail hit's your wallet! I believe Navistar is completely out of touch with their approach to emissions reduction.

 

Their sales are showing it as well. Last month Freightliner was hammering them. Sorry to be off topic. Let me round up a few questions for Paul.

1. Do the 2010 motors actually emit more NOx than a pre 2000 motor at the end of the turbo?

2. What is going to be the approach to clean the filter? Replace with a reman or a new DPF? What cost are we talking here.

3. Did Ford ever consider using extreme egr instead of scr? If so, what were your reasons to go with SCR.

 

Take a look at the file I have under the "First Read 6.7L Tech Folder" section. The last entry is a DEF summary (PDF file), look at page 5, it provides a general overview of why SCR is/was the best path for a number of reasons.

Your first question, I'm going to assume you meant pre and post 2010 vs. 2000. The primary driver for these systems is the result of EPA rules for 2010. Going back to the DEF summary again, page 3 provides a historical chart of emission level. NOx itself is a byproduct of high combustion temperatures. The turbo outlet temps are higher, to the point where exotic metals and ceramic are now being used vs. a few years ago. Horsepower & Torque goes up, temps go up, etc.

Question 2, the primary driver for what alternatives will be available is predicated on production / service volume. We studied a reman program early on, before launch, but couldn't justify one as there was no "core" available. "Core" meaning a stock pile of used aftertreatment components. This is typically seen in re-manufactured engine programs. You typically need a couple years of production volume to have enough material to begin such a program, again, based on volume.

What I suspect will happen is that the OEMs or a third party will eventually setup an exchange program. Pre 2011 was easy in that the DPF is bolted to the rest of the exhaust. There are cleaning machines available today that could be used. This is a picture of one that's available currently. Requires a 3 Phase power supply, compressed air, and venting. These were being considered being required for the Dealers, but was cost prohibitive considering that most would sit un-used for potentially years.

"The CombiClean™ (SEE ATTACHED IMAGE) is designed to clean both cordierite and silicon-carbide filter blocks between 3 and 20 litres capacity. The first stage of the cleaning process uses regulated compressed air to eject any excess particulate (soot) from the filter whilst drawing any ejected contaminant into a vacuum container. This is important as it eliminates operator exposure. Removing excess particulate prior to the heat cycle prevents excessive temperatures during filter cleaning. The second stage is the heat cycle that elevates the filter core temperature in a strictly controlled manner and passes air through the filter to provide the necessary combustion oxygen whilst ensuring uniform temperature distribution. In the third stage, following regeneration, compressed air is used in conjunction with the vacuum collection system to remove any remaining ash."

The newer aftertreatment systems w/ SCR, currently in use or will be used by most OEMs at some point will be similar to what you see on the 2011 Super Duty. Basically a torpedo that contains the Oxidation Catalyst, SCR catalyst and DPF all in one. This requires that the outer casing be "cut" at a pre-determined point to allow the DPF to be removed for replacement or cleaning. Initially there were flanges for each component, but 8" or 9" flanges between components are expensive, they can leak, but the biggest problem is that it increases the overall length of the system. So much so, that on the short wheel base trucks, the damn thing wouldn't package under the vehicle without reducing ground clearance by a considerable amount. That ultimately drove the decision on the design as it is today. So to reduce the impact of replacement, a service kit was developed that basically allows DPF replacement independent of the rest of the aftertreatment system. I haven't check the pricing as of late, but figure it being approx. 1/3 the cost of the total assembly. Another consideration was that once these emissions components are out of warranty, there's a certain percentage of customers who will just straight pipe them, at least until emissions testing rears its ugly head again.

Question 3, yes, back in 2006/2007 every option was being researched to determine how best to achieve the 2010 emissions standards. Prototype hardware was built for each technology that was promising. Dyno testing with instrumented hardware was used to prove out which was the most efficient, cost effective, etc. In addition, USCAR / ARB and CARB worked with the OEMs to develop the standards for common approaches to meeting emissions requirements. The two systems EGR & LNT (lean NOx trap) vs. SCR in the market place today was the result. The problem with EGR & LNT is that fuel economy takes a massive hit, and the precious metals in the LNT wear out over time making for a very costly repair. There's also the unknown of the cost and availability of those precious metals. So based on those factors, and many long hours/days/months of debate, SCR was determined to be the better solution, as least for Ford even with the cost hit for DEF. There's a possibility that small displacement diesels may use EGR & LNT at some point, but not for the >8500 segment.

Going forward, you will see hybrid systems that incorporate more EGR working in conjunction with SCR. Why??? LEV III emissions coming in around 2016-ish.

Hope this helps!

-Paul

 

>So much so, that on the short wheel base trucks, the damn thing would package under the vehicle without reducing ground clearance by a considerable amount.

I think you meant "reducing" ground clearance

Sam

 

Thanks for the great info Paul. What is your position at Ford exactly? Judging by your posts on FTE I would assume you built the whole new 6.7 solo. Whit the next round of emission standards coming I don't understand how they could clean diesel engines anymore? What are the requirements now, 0.2 NOx?


When you stated that after the DPF is clogged up and customers are switching to just straight pipes, did your team make it easier for a person to do this without causing CEL's and other problems? or I guess make it easier for a tuner to delete the system. Thanks again for the post. Great Info!

 

I don't believe the new standards have been officially released yet, I'll check when I'm back in the office on Monday. If I recall correctly, they were still being debated.

I'm afraid we cannot aid in such things. Large fines are levied by the government for emissions non-compliance and they don't want it to be easy to circumvent, even after the warranty period. What I was implying is that some customers will refuse to repair to oem specs. after warranty, mostly due to cost. However, the EPA, ARB and CARB continue to place increased monitoring requirements on the manufacturers. Wouldn't surprise me if one day there's some type of compliance monitoring off-board data transfer of a vehicles emissions to some database somewhere.

-Paul

 

Actually, it should have read, "wouldn't package" and has since been corrected.

Thanks!

-Paul

 

Heres that truck you were talking about Tom....

YouTube - Navistar MaxxForce 2010 Emissions vs SCR Round 2

 

Paul,

That's really an amazing amount of background information. Almost feels like a PBS NOVA or Frontline program that dives deep into all the technical and political aspects of meeting the EPA requirements. This type of insider view really helps one understand difficulties of balancing all these requirements while trying to deliver a mass-market product.

Is the current system solely Ford developed or was there any collaboration inside the manufacturing industry to settle on the current solution? Heaven forbid that Ford and GM would get together on something but I can scarcely begin to appreciate the value of the resources invested in this.

And Navistar's continued tantrum proclaiming that EGR solutions are better is simply getting tired. How long will they continue to scream that everyone else is wrong when it is they that are the only marchers in the parade out of step? Is it any wonder why Ford could not suffer the self-righteous sanctimony any more? Sheeze!

Epic