Regenerations how often?

There is no light or indication other than your fuel mileage dropping. Its hard to notice if your not sure what to look for.

Regen occurs every 375 to 400 miles or when soot mass levels demand it, whichever comes first. No bands play, no angels sing, it just happens whether you notice it or not.

Ok so the dic won't say anything then? I mean how are you suppose to know if it starts to regen then you shut it down right away because you got to your destination?

There is a slight increase in RPM. There has been a lot of discussion to search about the effects of turning the motor off during the regeneration.

Mine does it about every 1/2 tank (34 gal. tank). RPMs go up a bit, and if you have a good ear, the exhaust sound changes a bit of its tone.

yes, like it's been previously discussed, the more often you get the truck on the highway, the less often it will want to go through this regen process and the less % and fuel it will deduct.

My truck just went through one the other day, because I have been doing more city driving lately, the used oil life went down by 8 points from 80% to 72% and not to mention the 1.5 to 2 gallons that went to the regen Gods.

zr600 said:

Ok so the dic won't say anything then? I mean how are you suppose to know if it starts to regen then you shut it down right away because you got to your destination?

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Get an engine monitor like the DashHawk or Edge CTS........ Or just trust that GM designed it to do no harm......

zr600 said:

Ok so the dic won't say anything then? I mean how are you suppose to know if it starts to regen then you shut it down right away because you got to your destination?

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Only time youll get a DIC msg "CLEAN EXHAUST FILTER" is when the truck in not being operated in a manner that allows affective DPF cleaning. If this msg comes on, drive it above 30mph untill the msg clears.

Regens are based on, fuel used, engine hours, & miles driven. Happen once per tank full. I can tell its in regen by noticing, RPM is slightly elevated (@ idle) mpg drops, oil life % drops, engine sound (@ idle) & exhaust smell.

Mine regens when Iv used 16-19 gallons of fuel, thats 280-300miles since the last regen. I dont like to shut the engine off during a regen, so I get on the freeway & drive for 20 mins & that way it completes a regen right then & there.
Now when it goes into regen you dont have to stop everything just to complete the regen. Just keep driving until you get to your destination. It usually takes about 20-30 mins to complete a regen.

I've never noticed a regen while highway driving but they are pretty obvious when happening around town, as said rpms up slightly, throatier exhaust tone and if you shutdown and get out you will smell a burnt rubber smell. Also the exhaust will be ticking more as it cools. The regen process will start again next time you start up and are underway. Regen while towing seems to be passive because temps are hot enough to burn off soot. I don't know for sure that the duramax does a passive regen (no extra fuel dump to cause heat up) like semi tractors do- but I don't see why not. The fact you and your bud don't notice regen is as designed by gm - to be mostly transparent to the operator.

Well this just makes me want to get a delete and autocal right now i guess.

Paul Clancy said:

................ I don't know for sure that the duramax does a passive regen (no extra fuel dump to cause heat up) like semi tractors do- but I don't see why not. .............

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I did witness the "passive regen" DP peeps talk about a couple weeks ago. Was on a 700 mile one day freeway trip, watching on the DashHawk for the next regen that I knew was due at about 400 miles since the last regen. As I am climbing a long grade with sustained 1,000 degree EGT's, the soot grams were going down all that time. Then when the road leveled out and the EGT's came down, the soot grams began the normal increase.

Duramax-LMM said:

I did witness the "passive regen" DP peeps talk about a couple weeks ago. Was on a 700 mile one day freeway trip, watching on the DashHawk for the next regen that I knew was due at about 400 miles since the last regen. As I am climbing a long grade with sustained 1,000 degree EGT's, the soot grams were going down all that time. Then when the road leveled out and the EGT's came down, the soot grams began the normal increase.

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That would explain why I never hear or see signs of regen while towing.

Thanks

I hear a howling sound when mine is doing a regen at low speeds.

mikefos said:

Mine does it about every 1/2 tank (34 gal. tank). RPMs go up a bit, and if you have a good ear, the exhaust sound changes a bit of its tone.

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mine too

Twice a tank. A lot of stop and going driving.

dieseldan723 said:

mine too

Twice a tank. A lot of stop and going driving.

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Just curious, why do you still have a dpf? The Edge is such a dirty tune, that's probably why you are doing a regen so often.

Nearly all of my driving is either towing fifth wheel or putting around town and I still only regen every 375 to 400 miles, but I'm running all stock tuning.

Back when i had my DPF issues, a Gm rep told me by default, the LMM would regen every 410 miles no matter what the soot levels were.
For the first 20k miles he was about right as my truck would regen 405-415 miles every time. I have had the insight monitor from day 1 and logged every regen.

MRBASS said:

Back when i had my DPF issues, a Gm rep told me by default, the LMM would regen every 410 miles no matter what the soot levels were.
For the first 20k miles he was about right as my truck would regen 405-415 miles every time. I have had the insight monitor from day 1 and logged every regen.

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Tracked with the DashHawk and saw the same 410 miles here. Now at 50,000 on the odometer the regens come a little quicker if all around town driving (aging DPF?). Freeway driving still always close to 410 miles apart.

Duramax-LMM said:

Tracked with the DashHawk and saw the same 410 miles here. Now at 50,000 on the odometer the regens come a little quicker if all around town driving (aging DPF?). Freeway driving still always close to 410 miles apart.

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Driving home right after I posted this - notice higher idle and throatier sound - checked DashHawk - sure enough regen just stated - trip odometer read 335 miles since last regen - all around town. Reset trip odometer - next will likely be the same miles.