New Truck

[Moe19733]

I just ordered a new 2500HD Gas. I've been told to wait 8 - 12 months. Most likely will be a 2023. 

 

Should I replace the exhaust system with cat-back system? This is something I go back and forth on.

 

https://mbrpexhauststore.com/4-cat-back-exhaust-2020-2022-chevy-silverado-gmc-sierra-2500-3500-6-6l-t304-ss/

 

Perhaps someone that already has the new 6.6L could provide some perspective.

 

Thanks, Moe

[Trailblaster]

I removed the stock muffler and replaced it with a flow master 50 series. It lined up perfectly with the offset inlet/outlet at 3.5” diameters. I left the tailpipe as is and it took a muffler shop 20 minutes to cut out stock one and add 5” of pipe to flow master to connect. It didn’t require pulling anything or even adding or moving hangers. Pretty quick for a good welder. It sounds perfect too. This is on my 2022 6.6 gas LT crew cab.

Edited May 14, 2022 by Trailblaster

[KARNUT]

31 minutes ago, Trailblaster said:

I removed the stock muffler and replaced it with a flow master 50 series. It lined up perfectly with the offset inlet/outlet at 3.5” diameters. I left the tailpipe as is and it took a muffler shop 20 minutes to cut out stock one and add 5” of pipe to flow master to connect. It didn’t require pulling anything or even adding or moving hangers. Pretty quick for a good welder. It sounds perfect too. This is on my 2022 6.6 gas LT crew cab.

A procedure I’ve done many times with good results. My question is how does  it sound during deactivation mode?

[Kjduvall]

I did basically the same, used a borla xr1 round body 3.5 in/out. And ordered a 3.5in stainless section of pipe from summit racing and had it all welded. Sounds great and was pretty easy on the wallet. Really you just have to figure out what type of muffler you like. ( I suggest stainless no matter the style)

[garagerog]

2 hours ago, KARNUT said:

A procedure I’ve done many times with good results. My question is how does  it sound during deactivation mode?

Not for sure, but I believe the HD 6.6 gasser does have VVT, but neither of the cylinder deactivation modes AFM or DFM.

[Trailblaster]

No cylinder deactivation like the 1500 silverado.   It sounds amazing at cold start. It’s much better than hearing the loud fan too.

[Another JR]

8 hours ago, garagerog said:

Not for sure, but I believe the HD 6.6 gasser does have VVT, but neither of the cylinder deactivation modes AFM or DFM.

All of the above is correct. It also does not have auto stop/start. Here is a web page with information about the engine:

 

https://gmauthority.com/blog/gm/gm-engines/l8t/

 

[Moe19733]

Thank you

[Jagerschnapps1]

I have a 2022 gasser and have been contemplating changing the muffler. For those of you that have, how is the sound while on the highway? Can you talk comfortably on the phone at highway speeds with the windows up? 

[Kjduvall]

My borla xr1 is great sounding and not at all obnoxious. In cab is not loud at all , in fact mild by my standards but you can tell something has been done. On the outside its much louder, maybe thats a testament to how well insulated/built these trucks are. Heck I'm contemplating taking out the third cat to make it Evan throatier.