I am about 90% happy with my 6.7. I love the power and reliability thus far, but have one minor complaint... I'd probably be getting over 20mpg on my daily 30+ mile (each way) highway commute with my 3.55 rear axle; except the engine regens typically once/day either on the way to or from work. According to the Diesel Supplement, regens should only occur once/100-500 miles, not every 69 like I'm seeing. I would think "city driving" would equate to 100 miles, while highway driving would be closer to 500.

A few months back, during a 2500 mile trip towing an 8200lb (dry) TT and about 3400lbs of cargo, I think I only saw 2-3 regens TOTAL the entire 2-week trip. Additionally, my wife and I swapped vehicles for a weekend and she drove it distances about 2x as long as my daily commute at hwy speeds about 5mph higher than what I drive, and she saw about 2mpg more than me.

So, it appears that running with a load causes the regens occur less often (probably due to the already hot gasses passively burning off the particulates in the filter, whereas the unloaded running doesn't cause the engine to get as hot). Driving longer/continuous distance also appears beneficial. Are their any other secrets for getting regens to occur less often?

Aggressive acceleration? Higher highway speeds? Better quality diesel (I didn't notice a difference between Shell, Chevron, or AAFES [Military gas station])? Using the engine block heater to get the engine up to operating temp faster? (honestly, I know LITTLE about the intricacies of the heater since I live in a desert)

Just curious if anyone has "cracked the nut" (other than DPF Delete) or done any experimentation.

 

Similar commute for me as well, except I only regen about twice a tank. 150-200 miles between them or so, sometimes more sometimes less. Towing at highway speeds will cause the truck to utilize more passive regens due to your EGT being higher, so that is probably why you didnt see as much that time. Some people have said that additives and fuel choice play a factor; I haven't noticed cetane booster changing the frequency of regens much, but every now and then I'll get a bad tank of diesel and get more.

As far as the block heater goes; when I was in ak I would plug it in when the temps got around 10-15 F or so. It definitly helped warm it up quicker. Down around -20 she wouldn't reach full temperature, so it never regened until I would hit the highway.

If you search the forum for this there is a ton of info on the whole regen process that some smart people have dug up.

 

unloaded will produce less heat in the exhaust therefore needed an active regen.

so towing you are running hotter egts.

 

Heavy acceleration will produce more soot.
The extra heat generated by flooring it doesn't hang around long enough to do much good.
If you know you're close, that is one way to force it though.

If you want to know what's going on with the filter, you can purchase a device like the Edge Insight CTS (for the 2011).
That allows you to see the soot gpl and you will know when you are close to regeneration.
I purchased one for my 2011 awhile back because I wanted to know that type of information since I also use mine as a daily driver.

When soot gpl hits 2.66, the regeneration will begin within a few minutes.
Sometimes it begins right away, sometimes it's near 2.73 or so.
When it does this on the way home, which is most of the time, I just go for a longer drive.
You'll also see DPF temps remain high for several minutes after the regeneration process is complete.
By completing regenerations, my fuel in oil content is lower and I only have one per tank, not towing.

 

First off, like MPG, take what you hear on here regarding regen frequencies with a grain of salt.

My associate at work has 2011 F-250 which is literally identical to my 350; 4x4, CC, SB, SRW, 3.55 axle. He continually boasted about how he sees only 1 regen per tank. I was pulling my hair trying to figure out why mine was so different; same route, same fuel, same additives, same driving style. After nearly a year of this, I was bound and determined to figure it out. The only real difference was that I have an Edge CTS installed and he does not.

To make a long story short, we had an 1800 mile trip coming up which would consist of both highway and city driving, and we were going in his truck. I told him that I wanted to watch the soot levels in his truck to see how they differed from mine, so I quickly installed my CTS in his truck.

Well, guess what? His regen frequency is identical, IDENTICAL to mine! Soot comes up at the same rate, regen frequency is about the same. In city driving, average speed 35 MPH or less, long stops at lights, short duration travel time it was the same as mine; 50 to 70 miles between regens. Rural driving on 2 lane blacktop between 120 and 250. Pulling a trailer gave us over 300 miles, sometimes 550, but like my truck, a regen is forced before 600 miles for some reason regardless of soot level.

One year of trying to figure out the difference and there was none!

One thing that I did notice is that my regens go way up if I use an additive, especially Motorcraft PM22A. It's not quite as bad with Optilube, but still nowhere near as good as with just plain fuel. I also see less regens with winter fuel. I use Mobil diesel fuel.

With short trips of less than 10 miles, with cool downs between trips, you will see lots of regens. Probably less than 50 miles average between them. Not much you can do about it if you're in that situation though. But if you can get it warmed up, and you drive a mix of city and country 2 lane, you should see 120 to 160 miles between regens.

Are you using an additive?

 

I forgot to add that oil level is important too. Check it.

Some dealer service departments really overfill these things. I've seen trucks that show the level 1" or more above the full mark. My guess is that they put in 15 quarts instead of 13. This will dramatically increase the number of regens, especially at highway speeds.

 

Romeo-

Thanks! Sounds like you have the same truck setup as me. Ijust checked the oil level, and it was exactly in the middle of the markings atthe end of the 6 foot dipstick. I just had the oil changed last week for thefirst time, so we’ll see if that changes anything.

I really need to take her out on a long, unloaded trip tosee how she behaves. I seem to recall her regen-ing about every 120-150 mileswhen I was breaking her in driving the Tail of the Dragon x2 (I had 3-days toput 500 miles on her before my first tow), but since then I’ve only driven herunloaded on my daily 30+ mile commute. Any trip over 50 miles is generally towing about9,000lbs of TT. After unhooking at the destination, we usually only do shorter sight-seeing trips.

Other than high-fidelity engine monitoring, does the EdgeCTS buy you anything? I drive 90% of the time with the instant MPG called up,so I probably notice the regens more than most. It appears my MPG drops from 20to 14 for about 30 seconds before I get the “Cleaning…” message, then I cantell when it’s through b/c my MPG generally jumps to about 25mpg for a minuteor two afterwards. I still wish there was a consistent “Finished cleaning…”message. I actually saw one ONCE after I got a “drive to clean exhaust filter”message, but that was the only time I saw it. I’ve seen the truck ask me to “driveto clean” a couple times, but only saw the “complete” message once (even thoughI saw the MPG return to normal).

Does anyone know if stopping in the middle of the cleaningcycle is any better/worse for the engine/mpg than continuing to drive? I figure if it doesn’t finish on mycommute to/from, it will re-start and finish going in the other direction. Any fuel savings on the back-end from having already finished the regen is offset by the extra time/driving I didn't need to do on the front-side.

 

The regen process does not start back up when you start the truck up. It has to hit that 2.66+ soot level again before it activates.

Yes, stopping regens in process are harder on the engine/systems. When you put the truck in Park it should stop the regen process. When I have to do that I just let the truck sit and idle to cool off for a few minutes before I shut it down. The cooler (relatively) you shut off the engine the better, and a hot regen is not a good time to shut off.

 

One way to get less active regens is to keep the RPM's up on the engine around town. I lock out 6th, 5th and sometimes 4th when I know my speed won't be above 40mph, it makes a world of difference with little to no effect on mpg.

 

I monitor the regens with the edge insight. I used to see 200 - 300 miles before a regen. Now I am at 90-100 miles per regen. This means it is in regen 10 percent of the time. I will try the lockout and I will stop PM 22 to see what happens.


How is the XPD fuel supplement with regens?

No problems with towing. I get a forced regen about every 500-600 miles.

 

i have 1000 miles on mine and ive seen the cleaning exhaust filter or regen msg about 3 times so far, it only stays on the screen for a second and i dont notice any change in power or mileage, is that normal? are they two different things or am i confused?

 

sometimes people says they can notice the regen cycle.. I cannot.
If you look at instant fuel mileage, many times it will drop suddenly..
then come back 10 minutes later.. I watch the 5 minute average

 

this is my first new style diesel with the emissions BS on it so I know nothing about it, not sure if the regen and filter clean thing was the same or two different things and it flashed so fast I dont even remember exactly what the msg said but it was something about exhaust, I watched instant mileage when it popped on the screen for literally 2 seconds, i noticed zero change, I was cruising 68 with the cruise set.

 

'Cleaning Exhaust Filter' is the message on the console.
Regen is the technical term for what it is doing (regening the DPF filter).

the Diesel Particulate Filter (DPF) catches all the black smoke particles.. when it gets full enough, the regen cycle is started to burn up the smoke particles, and clean the filter, and start over again.

how often does it need to do that process? as soon as it gets full of course. more steady level driving produces less smoke, more stop & go, and hard accel more smoke..

 

ah, ok, thanks for clearing that up. I assumed that, but wasnt 100 percent sure. That explains why the one guy said he only saw it once very 900 miles and ive seen it 3 times in 1000, I tend to accelerate pretty hard, lol! Is the 2 second message flash normal? it said press ok to clear but it cleared itself before I could even press it. I noticed zero mileage change all three times.