I did a round trip to Houston the other day which is about 420 miles altogether. I run with auto regen turned off thanks to forscan. I hit full and did a regen on the way there, and then on the way back I forgot to turn off auto regen and she did another one. At zero % I turned off auto regen and then a hundred miles or so later she said 90% full.

I thought that was curious and resolved that I'm going to delete this truck. Then I hopped in last night to go somewhere and she only showed 60%, a little bit later on she only shows 35%. But auto regen is off all this time.

Can the DPF percentage full go down without a regen? Or is my truck going wonky? I'm getting tired of all this regen stuff, every time it runs seems like it uses over a gallon of diesel.

This is my 2018 dually, and she almost never sees the city. I drive on country roads and freeways.

 

Sure it can go down. There is active and passive regen. Active is when the computer tells the system to regen. This will occur at no more than every 500 miles since the last active regen regardless of what percentage full the filter states. Passive regen is what occurs as you're driving the truck under certain operating conditions. Normally, you will be passively regenerating if you are pulling heavy. Whatever condition raises exhaust gas temp in the filter to the level it burns off soot is passive regeneration.

Your owner's manual fully explains the diesel emission control systems and how they operate.

 

Going down from 90% to 35% is a first, since I set it to manual regen a few months back and have been watching DPF status. It's back up to 70% again this morning, as soon as I fired her up. Was 35% when I parked last night.

I find this all very curious.

 

I've never seen the dash percent go down without a regen. In forscan, then CL soot goes down without a regen, but that doesn't impact when a regen happens because the OL always hits 100% first. The dash display is based on the OL soot. I don't think I've ever seen IL decrease via passive regen, but maybe I've just never observed it.

BTW, I assume OL and CL are open and closed loop, but am not sure.

 

I do hate these systems. Granted, they perform as intended and as designed but, I still hate the entire purpose and the way they function. I know others have chimed in regarding cleaner air and reduced pollutants but, I would argue that the manufacturing process and the burning process completely negate any environmental benefits that the engineers intended. These trucks run very clean now anyway (unless you intentionally make it roll coal - which puts all diesel owners in a bad light).

I have 48k miles on my 17 now and the regen ALWAYS stops at 20% then it will residually burn down to 16-17%. I have a feeling that there is a portion of the particulate matter that is permanently in the filter now, incapable of being burned off - and it will need to be “replaced” at a certain point. The starting place for my regens vary, sometimes it reaches 95% full and sometimes it’ll start a cycle at 65% full. I have 80-85% interstate miles and very little towing. Just patiently waiting for the right time to tune it up.

 

Tell you what, you and me both... It kills me to see my avg trip mileage go from 15.6 down to 14.2 in 15 minutes of flat country driving. As for the environment, doesn't burning more fuel crisp the environmentalists' tacos, as it were? Seems that they would hate that too. There's a youtube guy who did a lifetime analysis of the extra fuel that all the regens consume, and it was monstrous. He decided to delete. I'm not even going to wait out the warranty. The dummy DPF you can install yourself, and the rest of the job is done with a good scan tool and tuner...almost all done in software, iirc. Once my warranty is gone, I plan to do a physical EGR delete so there's room in the V for a true exhaust gas pyrometer. Having that on my 7.3 has been a useful tool in preserving the turbo to 260k miles so far with no signs of wear or oil leaks.

 

One thing you can’t argue with about these systems when working is their emissions are very clean. My old 2005 6.0 idling in the garage or outside, would gas you out. In the camp ground idling, and everyone would be complaining. Loved that truck. But in comparison, the old truck exhaust pipe was black inside by 20,000 miles. Your eyes would burn from the axhaust in minutes.

my 2017 has 50,000 km and the inside of the tail pipe is clean, it can idle in the garage for a long time, you can’t even tell it’s diesel exhaust, can’t smell it, doesn’t burn your eye. It would be interesting to see and monitor if you remove these systems how quickly this would change.

i will consider deleting but not until my extended warranty is up, or I have major troubles. So far, yes, it must run auto regents every 500km, which is too much, and results in wasted fuel. But this does keep it cleaned out in the DOF in particular. If your messing with these systems, be careful that you regen enough to prevent the DOf getting too plugged as it will have to come off and be put on a machine to properly burn it off.

 

Is it 500km or 500 miles? I'd heard that latter, which is why I griped about 2 regens in a 400 mile drive.
As for your clean exhaust pipe, that sucker gets so hot that it probably burns out any traces in there!

But that said, my 6.0 and 7.3 both have exhaust pipes that are as black as can be.

 

Back pressure sensor in the exhuast system informs the computer of your dpf status.


If your heavy footed and punch it a lot you could be sending high back pressure signals to computer .

 

Nair, mate. Got my tuned 7.3 for that if I want it. The 6.7 is driven lightly. Up to 17mpg from a dually.
I suspect that driving gently might actually load up the DPF quicker, due to lower exhaust temps.
But on this particular road trip it was freeway speeds almost all the way.

 

I’m in Km up here in Canada and it seems it’s between 400 and 500 km it is doing mandatory auto regents. I would be happy if it was more like 600-800 or better as needed only. You really do notice the fuel consumption issue after a while. And I am paying $130.9 per litre, at 4.4 litre per gallon, so $5.75 Cdn per US Gallon, so that sucks on a 49 gallon Long box tank.

the love a diesel ain’t cheap.

 

I found a way to make regens happen faster. Go uphill in 4th gear at 70 mph for 10 miles. LOL, that was just luck to find myself there at the right time. Got down to 10% DPF.

Anybody know a good source for step-by-step delete instructions? There are a lot of goolagtube videos for the earlier trucks, but not for 2017+

 

get forscan and run a manual regen

once it finishes drive it for 10 minutes

lowest I have it hit was 4% then drove it for 10 minutes and it dropped to 2 %

 

I run manual regens. Have hit 0% but only when on long TX drives. Below 45 mph the regen seems to stall. YMMV.
That % DPF reading is clearly delayed, btw. If you compare instant fuel consumption against it, there are 5-10 mins of delay.

 

DELETE DELETE DELETE!
Its the best thing you can do for your engine. It will love you back to the tune of 20mpg or more at 70mph.

Deleted my 18 dually at 4,000miles on the clock and I'm so glad i did!
I have a HP increase delete tune and get terrific fuel mileage and shrink my energy consumption by 40%. Use less fuel, use no DEF. so the DEF companies have a smaller carbon footprint bc they dont have to drive or ship DEF to a store for me. Fuel companies dont have to refine and ship as much fuel for my truck. Win win. Yes it will stink like an old diesel does. Love the smell.

70MPH = 19-20mpg.
65MPH = 20-22mpg
55mph = 25+mpg. No BS.
I drive all over the country and those numbers don't always hold true if driving in hilly places or in higher elevation areas.

When the truck was stock, 15mpg average at 70mph was the best i ever saw on the mpg meter. Thats garbage and a waste of energy no matter how its sliced.
Either clean exhaust out and waste fuel, or slightly dirtier exhaust out and less fuel in. All seems moot to me at the cost of our bank accounts. We pay for that stupid system in the cost of the truck. Then gotta pay more money to get rid of it. How is producing more parts and using more fuel and producing billions of gallons of DEF fluid and billions of gallons of extra diesel fuel not bad for the environment? Absolutely absurd. We've all been hoodwinked by these crazy socialist democrats with the narrative of its for the kids to have clean air. Blah. Go after China then. They are the worlds biggest polluters, PERIOD.