Particulate filter

[FishermanJer]

My filter on the display is saying it's at 50 percent. What's the best way to get it back to 0%? I have a 2021 ram 2500 diesel Laramie

 

[fuchsroehre]

Not sure it is required at 50% but below is what you should do at 80%. Could be possible that nothing happens at 50% when you perform the below steps. Not sure.

One section states:
The Cummins® diesel engine meets all diesel emissions standards, resulting in one of the lowest emitting diesel engines ever produced. To achieve these emissions standards, your vehicle is equipped with a state-of-the-art engine and exhaust system. These systems are seamlessly integrated into your vehicle and managed by the Powertrain Control Module (PCM). The PCM manages engine combustion to allow the exhaust system’s catalyst to trap and burn Particulate Matter (PM) pollutants, with no input or interaction on your part.

 

[FishermanJer]

Not sure it is required at 50% but below is what you should do at 80%. Could be possible that nothing happens at 50% when you perform the below steps. Not sure.
View attachment 30658

Thank you, I need to go for a drive then and see.

 

[Nick]

I wouldn't worry about it until it gets to about 80 . Usually around 50 or so mine will regenerate . If you put a load on your truck it will regenerate really quickly. It should throw a code if there is a malfunction in the system .

 

[FishermanJer]

I wouldn't worry about it until it gets to about 80 . Usually around 50 or so mine will regenerate . If you put a load on your truck it will regenerate really quickly. It should throw a code if there is a malfunction in the system .

OK thank you

 

[Will_T]

My filter on the display is saying it's at 50 percent. What's the best way to get it back to 0%? I have a 2021 ram 2500 diesel Laramie

Mine is never detectibly over 0%. I used to wonder if it was even working but others have reported theirs are the same. So trucks vary for some reason I guess. May be driving habits, but my truck is about 70% towing, 30% around town.

 

[FishermanJer]

Mine is never detectibly over 0%. I used to wonder if it was even working but others have reported theirs are the same. So trucks vary for some reason I guess. May be driving habits, but my truck is about 70% towing, 30% around town.

I tow all the time in the spring and summer and fall. Winter is the only time I don't tow. So it's probably in need of a good work out.

 

[FishermanJer]

So I hooked up to my ATV trailer and took it up the mountain. The particulate filter now says 0. Thanks to all!

 

[Darmichar]

Not entirely sure how Cummins manages their DPF's. I work for Caterpillar and on most of the Tier 4 systems we have, they won't do anything actively with the DPF until it reaches 80% as well. Once it reaches that point, it will actively regenerate the system. You can passively regenerate by loading the engine (pulling a relatively heavy load) for an extended period of time which will increase the heat in the system enough for it to regenerate passively.

 

[superjoe83]

Not entirely sure how Cummins manages their DPF's. I work for Caterpillar and on most of the Tier 4 systems we have, they won't do anything actively with the DPF until it reaches 80% as well. Once it reaches that point, it will actively regenerate the system. You can passively regenerate by loading the engine (pulling a relatively heavy load) for an extended period of time which will increase the heat in the system enough for it to regenerate passively.

There are two triggers that can initiate a regen on these trucks, the first one is a timer in the ecm, about every 25 hours of engine operation it will trigger a regen, no matter what the soot load is.
The other trigger is soot load
On a properly running truck that is driven normally and not short tripped or excessively idled the timer will be the normal trigger

 

[Darmichar]

There are two triggers that can initiate a regen on these trucks, the first one is a timer in the ecm, about every 25 hours of engine operation it will trigger a regen, no matter what the soot load is.
The other trigger is soot load
On a properly running truck that is driven normally and not short tripped or excessively idled the timer will be the normal trigger

Good to know. I deal with "off road" engines so they are handled a little differently. This is my first diesel truck and I wasn't sure how Cummins managed the DPF on them.

 

[H3LZSN1P3R]

I wouldn't worry about it until it gets to about 80 . Usually around 50 or so mine will regenerate . If you put a load on your truck it will regenerate really quickly. It should throw a code if there is a malfunction in the system .

Yea my driving habbits consist of the throttle being an ON/OFF switch so thats most likely why the gauge has only moved slightly once

 

[Brewbud]

Yea my driving habbits consist of the throttle being an ON/OFF switch so thats most likely why the gauge has only moved slightly once

Same. My truck typically only sees short trips. My gauge has never climbed above zero. It is not driven with a light foot though. Regens only every 24hrs of engine hours so far.

 

[fuchsroehre]

Not sure if he's 100% correct, but he sounds confident LOL.
What I understood is that there are pressure sensors before and after the DPF which are used by the ECU.

 

[Darmichar]

Not sure if he's 100% correct, but he sounds confident LOL.
What I understood is that there are pressure sensors before and after the DPF which are used by the ECU.

His descriptions of the system and how they work are actually pretty accurate. The retarding of the timing also allows more 'raw' fuel into the exhaust stream that catalyzes on the DOC and helps to increase heat in the system prior to entering the DPF.

 

[Darmichar]

If you have 5 minutes, this video from Cat gives a good overview of how an aftertreatment works. This is how most systems work, but may change slightly from Manufacturer to Manufacturer.
When I first started working with Dealers troubleshooting these systems, I spent a day with one of the primary Engineer's responsible for Cat's aftertreatment design.
He sent me the link to this video to help me better understand what was going on.

 

[fuchsroehre]

If you have 5 minutes, this video from Cat gives a good overview of how an aftertreatment works. This is how most systems work, but may change slightly from Manufacturer to Manufacturer.
When I first started working with Dealers troubleshooting these systems, I spent a day with one of the primary Engineer's responsible for Cat's aftertreatment design.
He sent me the link to this video to help me better understand what was going on.

Really nice video. Even showed it to my son (11y), he was interested and asked a lot of questions.
I think before watching the video it is good to understand what is bad for the human body. NOx, CO, black particles.
Also that video is recommended for people who always mix up the DPF and the DEF system (or throw it all in one basket). DPF always reminds me on an oven in the kitchen where you can set the self cleaning option and it runs for very high temp to clean itself.
I do not fully understand why the DOC is removed when some vehicles are "deleted". Even deleted the DOC should work converting bad CO to the harmless CO2. Maybe I am wrong and the DOC stays in.........

 

[MEGA HO]

I don't think my truck has timer for regens. Mine is 2019 and I told the dealers not to flash / update my ECU, and they didn't. I've been hearing about these "timers" and been driving my truck all of the last summer watching the DPF gauge like a hawk. Nope, no 24hrs engine hrs regens.

 

[Brutal_HO]

I don't think my truck has timer for regens. Mine is 2019 and I told the dealers not to flash / update my ECU, and they didn't. I've been hearing about these "timers" and been driving my truck all of the last summer watching the DPF gauge like a hawk. Nope, no 24hrs engine hrs regens.

I think if you were monitoring the DPF EGT's inlet vs outlet and pressure differentials you would see otherwise.

If a flash does anything, it's making the gauge more accurate and truthful.

 

[MEGA HO]

I think if you were monitoring the DPF EGT's inlet vs outlet and pressure differentials you would see otherwise.

If a flash does anything, it's making the gauge more accurate and truthful.

Some others have reported 24 hrs regens and by that I guess they talk about active regens. I have had the DPF gauge screen on and watched it when it was supposed to roll over 24 engine hrs, and nothing has happened. Did it often enough to confirm it's not happening and my DPF gauge was not always at zero at those times. I only ever see regens when the gauge reads sort of 50-60% full, never had it much higher than that, definitely not 80% full.
Other times my gauge may be partially full and I would take a long multi days trip somewhere and see it slowly dropping down to zero without active regens.