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6.2 owners - Dual or Single Flapper

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BluegrassMotorsport Enthusiast

BluegrassMotorsport

Posted
Posted
55 minutes ago, JohnH4260 said:

How does one delete or get rid of the flapper? 

Any muffler shop can get rid of them and weld pipes back in their place, especially if you plan on removing or replacing the muffler. A good aftermarket catback system will also take care of the flappers. I'll say this - there's an incredible difference in the way these trucks drive with the flappers gone. I did the muffler delete and left the flappers and have since moved to the Corsa catback system. It's a different truck now. 

  • Like 1
JohnH4260 Enthusiast

JohnH4260

Posted
Posted
10 hours ago, kodiakdenali said:

Very strange...2020 Denali, I only had 1 flapper.

now I have 0 ?

How did you get rid of it?

kodiakdenali Enthusiast

kodiakdenali

Posted
Posted
26 minutes ago, JohnH4260 said:

How did you get rid of it?

Installed a borla atak cat back.

You can lock them in the open position to get a bit more sound but that wont completely remove the restriction. To remove it without doing something like a cat back would requiring cutting that section of the pipe out and welding in a new piece.

Although if a cat back fits your budget there are many other benefits over just removing the flapper.

  • 2 weeks later...
Leevon Enthusiast

Leevon

Posted
Posted

I had two on my 2020 6.2L Trail Boss LT.  I deleted the muffler and both flappers, it was too loud so I put one back and now it's perfect.  

Troger Enthusiast

Troger

Posted
Posted (edited)

Does anyone else notice this noise when in 4 cyl or less than 8 cyl mode?  Wondering if it is due to the flapper or flappers.  Edit:  Not my truck, found this on another thread, but sounds just like mine.

 

Edited by Troger
MG386 Enthusiast

MG386

Posted
Posted

2020 AT4 6.2. build date Nov 2019. It had 2 flappers before I installed the GMPE. No drone btw.

Sent from my Pixel 5 using Tapatalk

  • 1 month later...
  • 1 month later...
Firehawk99 Enthusiast

Firehawk99

Posted
Posted (edited)

I have a 2021 Trail Boss 6.2 and I only had one flapper before the muffler. This is what I did to get rid of mine. I cut all the 3" out and replaced it with a 3.5" Vibrant 304ss muffler and 304ss tubing. I debated getting the Borla touring cat back but I had a hard time justifying the cost. Plus i wanted to keep the resonators.

 

Edited by Firehawk99
.
bjr2020 6.2 Enthusiast

bjr2020 6.2

Posted
Posted

2020 tb custom 6.2 had 2 flappers did afe muffler delete left 1 flapper wound it so it’s always open

  • 2 years later...
typhoon186 Enthusiast

typhoon186

Posted
Posted

They got an award for making something that chokes the engine and kills performance.   Wow. 

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