I have searched the internet and this forum and I cannot really get a clear undertanding of the "regen" aspect of these vehicles.

I am in the process of purchasing a 2011 but I like to be as well educated as I can as this will be my first diesel truck.

Maybe someone can give me a link to read up on this regeneration problem!

Thx

 

Here's a link to a thread:

https://www.ford-trucks.com/forums/9...011-6-7-a.html

 

There is no Regen Problem. There is a Regen Process.

There are two emission processes that take place in the exhaust system.

Regen is the process of buring of excess soot. The black smoke that you see on older diesels. This is acomplished by collecting the soot on Diesel Particulate Filter ( DPF) When the soot levels reach a certain level, The computer triggers a Regen. The engine then sends fuel down the exhaust pipe that is used to increase the tempeture high enough to burn off the soot. This is done by using 4 of the injectors. ( I forget which 4) to inject fuel on the exhaust stroke. On the 6.4L engines in the 2008-2010 trucks, They used all 8 injectors and their was some lag in power and oil dilution from excess fuel. The 6.7L has solved both of these problems with better engineering.

Additionally, the 6.7L engine utilizes a second generation of Regen. It is smarter about how and when to regen. It will utilize Passive regen when possible. Think of this as system utilizing already hotter temps when you are working the engine hard. i.e. towing. Folks who are working their trucks don't see Regens as often as Soccer Dad's who are using their trucks as daily drivers and not getting higher EGTS because of the light work.


The Regen process in a 6.7L is pretty painless. Most will never notice that it happens unless they see the message flash on the command center or watch their instant fuel mileage. ( The fuel mileage will drop for the 5-10 minutes that the regen is going on.) There is very little noticable engine preformance drop during the regen.

If you happen to drive a short distance during the Regen process begins and it doesn' have time to complete. The soot will build up and at some point the command center will display a message of "Drive to Clean " meaning that instead of shutting off the engine while the regen is still in process, You need to keep driving a little longer. In 26,000 miles I've seen this once.

My truck sees and average distance between regens of almost 300 miles.

The second part of the emissions, is the SCR. This is new to 2011 trucks and was not part of any previous generation. This reduces the NOx emissions. NOX emission are more prevelant at higher exhaust temps, Previous engines dealt with this by utilizing a EGR. That would recirculate exhaust gases into the combustion chamber to lower combustion temps. This process was hard on fuel mileage and the EGRs had a tendency to plug up. You will see a lot of comments about EGR deletes on 6.0L engines as users tried to deal with the problems they caused. The 6.7L inject Diesel Exhaust Fluid ( DEF) into the later part of the exhaust system. This is basically the same technology as smoke stack scrubbers on factories. The DEF reacts with catylist in the exhaust system to reduce the NOX. Again this is pretty much a Non-Event. The computer handle the process. The 6.7L will consume about a gallon of DEF per 1000 miles and has a 5.x gallon tank. The main concern with DEF is that it will Freeze @ 13*F. So you don't want to over fill the tank and have DEF in the plastic line that runs between the filler opening and the tank.

DEF has been readily available at most truck stops, parts stores and Walmart.

Now there are those who install programers and remove their exhaust system. Some of those folks just like to see black smoke come from their trucks, Others are searching for better fuel mileage by not injecting extra fuel into the exhaust for the regen process. Most folks are just enjoying their trucks and not paying much attention to either process.

 

Thx for the awesome clarification. I have read up on the DPF and the DEF uric acid so I have some basic knowledge. These new admissions are the only reason I can drive a diesel! Diesel fuel and that black exhaust have always made me feel ill...even as a kid. So that's why I have never owned a diesel! I pick my 2011 CC up WED!!!!!

 

Congrats on the new truck! I am glad to hear that the DPF has a positive benefit for you. A lot of us, including myself, forget about how important something like this can be to others.