3.0 liter gets pretty noisy during regen…

[64509chvl]

I just got my gmc slt 3.0 liter a week ago & really like it.  Came from a 3/4 ton but really enjoying this little guy!  
It went into a regen over the weekend & I noticed 2 things change.  The mechanical Diesel engine sound was way louder & the exhaust tone was much deeper, more of a drone in the cab.  When the regen was done, it was back to normal.  Is this a common trait of regens in the 3.0 liters?

The dash did tell me to keep driving until it was done, so I did lol.  

Thanks for any info!

[redwngr]

If you had a 'keep driving' message, it was way beyond the usual soot level for starting a regen.

 

There is no message during a regular regen.

On LM2 I don't notice a change in sound when driving -- but do notice exhaust sound when idling.

 

For entertainment I decided to get an aftermarket obd port monitor.

 

Normal regen on LM2 is quicker than the 6.6's I ran.

On LM2 it only lasts 11 or 12 miles. 

If interrupted, it will resume the regen soon after starting the next trip.

If the regen was close to finished when parked, it not resume.  Of course this means the next one will start a little sooner. 

 

Daily driving I usually get regens in the 200 - 300 mile range.

When it's working harder it and has higher exhaust temps it seems to passively regen and results in intervals can be 600+ miles.

[64509chvl]

Right on thanks for the info!  Gotta get more miles on it.  I may have just noticed more diesel mechanical noise from the engine as a coincidence.  Maybe they just are louder at some times than others.

[OliverDennis52]

I've noticed that there is a bit more of the diesel clatter under low throttle during regens.  As soon as it's done, it quiets right down.

[64509chvl]

8 hours ago, OliverDennis52 said:

I've noticed that there is a bit more of the diesel clatter under low throttle during regens.  As soon as it's done, it quiets right down.

Thanks bud, appreciate the response!  I’ve had 4 different 3/4 ton diesels…2 with DEF & never noticed a change in sound like this on regen with my other DEF rigs.  Just seeing if it’s a normal thing for these guys, I called the dealer & Ofcoarse they say it’s normal lol

[gemarsh]

5 hours ago, 64509chvl said:

Thanks bud, appreciate the response!  I’ve had 4 different 3/4 ton diesels…2 with DEF & never noticed a change in sound like this on regen with my other DEF rigs.  Just seeing if it’s a normal thing for these guys, I called the dealer & Ofcoarse they say it’s normal lol

DEF doesn't have anything to do with the regen.

 

What your hearing is your fuel mileage tanking, thanks to the epa, cleaning your soot filter.

[64509chvl]

3 hours ago, gemarsh said:

DEF doesn't have anything to do with the regen.

 

What your hearing is your fuel mileage tanking, thanks to the epa, cleaning your soot filter.

So you notice your motor mechanical sound being more pronounced during a regen aswell?

[Dirk13]

10 hours ago, 64509chvl said:

So you notice your motor mechanical sound being more pronounced during a regen aswell?

Normal. Mine does it too

[Dirk13]

To save your next question, the burning smell is normal too. 

Edited September 30, 2021 by Dirk13

[redwngr]

50 minutes ago, Dirk13 said:

To save your next question, the burning smell is normal too. 

Only for the first one or 2 regens...

[Dirk13]

1 hour ago, redwngr said:

Only for the first one or 2 regens...

Meh, it was definitely most prominent on the first couple, yeah. But I catch a whiff of it still occasionally if sitting still. 

[64509chvl]

4 hours ago, Dirk13 said:

To save your next question, the burning smell is normal too. 

Lol thanks!  You can definitely smell it on all of them .  Thanks bud!

[64509chvl]

5 hours ago, Dirk13 said:

Normal. Mine does it too

Thanks for the info

[KARNUT]

Most who read my post realize I’m not fond of most of the newer trucks. My mother still drives her 01 diesel Ford. Her other truck is a 98 Ram diesel. That’s about the time I quit driving diesels. My fond memories of the smell and clattering sounds of power. I put about one million miles on diesels pulling my campers and equipment. They use to be bulletproof. Even after many mods. I know lots of people who drive them. They usually need major work on their pollution devices at around 100K miles. It ain’t cheap. Most delete. There’re still bulletproof. The add ons aren’t. Maybe there’re needed. You’ll never get the straight scoop. But like cylinder deactivation. Its an extra expense. That’s hard on the wallet.