How does regen work on the newer Duramax diesel? I have a 2013 that just turned 10,000 miles. I have noticed when the engine runs at a higher idle rpm when driving around town for a while. Running at highway speeds, sometimes in 5th gear, when the engine idle is elevated and the rpm returns to normal.We are in our 3rd week of being on the road. Between campground stays, we take day trips and the usual driving around town for a few days. Yesterday we towed 90 miles with average speeds of 60 mph. Today we took a round trip of 60 miles with speeds of 65-70 mph. When getting back into town and prior to fueling I noticed the rpm were around 900 instead of the normal 600. Not knowing much about the regen, I assumed that sustained highway or elevated rpm's would clean the system but that is apparently not the case, No indication on the dash of anything abnormal.Enlighten me.

Mine regens approx every 400 mi. When in regen it will idle higher to keep exhaust temps up. It sometimes can take 30 or so mi for it to complete a regen at highway speeds. There is really nothing to worry about and if you drove enough short trips for it to be a problem the DIC will warn you. I have 68,000 mi on my 2011

Thanks Nick but that is where I am confused. After a speedy 30 miles on the highway, we drove into town for a few miles, walked the shops and then ran another speedy 30 miles when I saw it was doing a regin. I have noticed a few of the regins previously without highway miles but have no idea how often it does and apparently have not noticed most of them.

I use and Edge Insight monitor, and it shows when my truck goes into regen.Regardless of what load I have or don't have, it does a regen once every tank of fuel (long bed = big tank)The comments I read on the various Duramax forums are the same as my experience - about once every tank of fuel it will regen.

Charlie D. wrote:Thanks Nick but that is where I am confused. After a speedy 30 miles on the highway, we drove into town for a few miles, walked the shops and then ran another speedy 30 miles when I saw it was doing a regin. I have noticed a few of the regins previously without highway miles but have no idea how often it does and apparently have not noticed most of them.The exhaust has a differential pressure sensor in it, one sensor before the dpf one after. When the soot level builds up it creates a pressure difference. When the difference hits the programed point it triggers a regen.

Also, if you shut the truck down mid-regen, it will begin all over again when restarted, rather than resume as far as I know.

Regen | Good Sam Community

N-Trouble
Explorer
Apr 07, 2014
I have a Edge CTS on my 2012 Duramax so I see all this stuff. Current LML Duramax initiates Regen when soot grams hits right around 43g and will continue the regen process until it drops down to anywhere from 0-6g of soot. Soot grams is based on differential pressure sensors in the DPF as explained previously.

Without a CTS the only way to identify the truck is in regen is elevated idle, louder engine (due to 9th injector), or DPF smell when exiting the truck.

If you have to stop mid way in a regen cycle it will pick back up where it left off. However the more stops the longer its going to take to complete as it has to build the heat back up each time.

GM designed the regen process so that it would be invisible to the driver. THey did not include any dash messages to indicate to the driver that the truck is in regen.
machunt
Explorer
Apr 07, 2014
the only way to tell is the rpm,s?
chevor
Explorer
Apr 07, 2014
A new one.
FishOnOne
Nomad
Apr 07, 2014
chevor wrote:
First regen on my 13 was @ 800 miles on odometer, second was in regen just before 1600 miles. You have to use an aftermarket reader to know when this happens.
My 2010 regens 400 miles. It gets shorter as DPF ages. I'm on second DPF on the truck. Original replaced @ 470,000 miles. Truck would regen under 200 miles empty and under 100 miles pulling.

470,000 miles on a DPF is pretty impressive. Did you purchase a new DPF or had your original one reworked?
chevor
Explorer
Apr 07, 2014
First regen on my 13 was @ 800 miles on odometer, second was in regen just before 1600 miles. You have to use an aftermarket reader to know when this happens.
My 2010 regens 400 miles. It gets shorter as DPF ages. I'm on second DPF on the truck. Original replaced @ 470,000 miles. Truck would regen under 200 miles empty and under 100 miles pulling.
FishOnOne
Nomad
Mar 16, 2014
gmcsmoke wrote:
no, GM's monitor soot levels and will regen down to 20 grams or so. if you stop mid way it will resume and finish when the soot level reaches a predetermined level.

Agreed... And GM has the best regen setup with utilizing a ninth injector to perform this process which prevents oil dilution.
gmcsmoke
Explorer
Mar 16, 2014
no, GM's monitor soot levels and will regen down to 20 grams or so. if you stop mid way it will resume and finish when the soot level reaches a predetermined level.
ib516
Explorer II
Mar 16, 2014
Also, if you shut the truck down mid-regen, it will begin all over again when restarted, rather than resume as far as I know.
timdan94
Explorer
Mar 16, 2014
Charlie D. wrote:
Thanks Nick but that is where I am confused. After a speedy 30 miles on the highway, we drove into town for a few miles, walked the shops and then ran another speedy 30 miles when I saw it was doing a regin. I have noticed a few of the regins previously without highway miles but have no idea how often it does and apparently have not noticed most of them.

The exhaust has a differential pressure sensor in it, one sensor before the dpf one after. When the soot level builds up it creates a pressure difference. When the difference hits the programed point it triggers a regen.
deltabravo
Nomad
Mar 15, 2014
I use and Edge Insight monitor, and it shows when my truck goes into regen.

Regardless of what load I have or don't have, it does a regen once every tank of fuel (long bed = big tank)

The comments I read on the various Duramax forums are the same as my experience - about once every tank of fuel it will regen.

Forum Discussion

Regen

About Travel Trailer Group

Related Content

Rocket exhaust from diesel regen

2019 Duramax Regen

Diesel Regen Smells

deisel regen

3 regens in 300k