Muffler swap on 6.2l

[mjdxtreme]

Ok guys I have been wanting to get a little more rumble out of my 2015 sierra denali with the 6.2l. Now I dont want to drop the coin on a full cat back system as I feel the stock piping is sufficient. I also plan to keep the flapper to avoid the v4 drone. So what I am looking to do is just cut the muffler out and put a new one in it's place. Now I was looking and noticed the piping is 4 inch. All I have been able to find is 3 inch inlet and outlet. Those that have done just a muffler swap, what have you used. Want to keep it mild but want a good rumble under heavy throttle. Thanks in advance.

[country_09]

Pipin on my 6.2 is 3.5". I bought a magnaflow 12909 I believe. 3.5" in/out

[Rawyzf]

I thought they were 3.5" for the 6.2.

 

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[mjdxtreme]

I will look into the magnaflow 12909. Did you just muffler swap or did you remove other components. I could be wrong on my measurement. I got under their pretty quickly as it was still hot from driving it. And tried to eyeball it with my tape measure.

[emeryz28]

this subject has been beaten to death. I have read countless threads, but I am right there with you. My truck whispers and my neighbors wife has a Denali with the previous gen 6.2 and stock it sounds awesome.

 

many guys on here just cut out there muffler and had a shop weld in a straight pipe for like $60 and I have not heard anything but good reviews of this. Obviously they left on the flapper and the resonator. I am going to try this.

 

Right now I have my flapper clamped open and it actually made the exhaust louder, especially on startup and you don't hear that metal clunk of the flapper

[Lgetz]

MJDX I installed the Magnaflow 12909 in my 6.2 and am quite happy with it. Minimal chopper sound in V4 mode and no droan cruising at 70-75 mph. Nice deep tone and makes the right sound at startup.

[mjdxtreme]

Lgetz did you remove the flapper or resonator as well or just swap the muffler leaving the flapper and resonator.

[volcom8190]

you can always get a set of headers like i did. Even with cats its more than loud enough for my taste with the stock catback. I had to take my corsa off because of noise complaints, and the fact if i used more than 30% throttle it would wake the dead.

[Lgetz]

Lgetz did you remove the flapper or resonator as well or just swap the muffler leaving the flapper and resonator.

Flapper valve was eliminated but resonator remained in place. If shop is diligent they can measure everything precisely and simply cut off the OEM muffler and flapper valve. No additional piece of pipe will be required to weld the Magnaflow in its place.

[Rawyzf]

you can always get a set of headers like i did. Even with cats its more than loud enough for my taste with the stock catback. I had to take my corsa off because of noise complaints, and the fact if i used more than 30% throttle it would wake the dead.

 

I did the exact same thing, except with Borla catback. It was too loud after headers.

 

Headers are great, as they actually have more than just a sound benefit. However, you have to be willing to risk your warranty and you have to get a tune. (Both obviously fine with me)

[Guapoh]

Here you go. I have same truck and engine. I did keep the OEM valve flapper.

 

This is what you want.

 

 

[mjdxtreme]

Here you go. I have same truck and engine. I did keep the OEM valve flapper.

 

This is what you want.

 

 

That sounds good. How is the drone and interior cab noise when just cruising.

[TJay74]

I have used the MF 12909 on both of my previous 6.2 trucks, both had the flapper cut out and the rear resonator cut out. Both sound perfect that way.

[Guapoh]

No drone. I kept the flapper.

[JCunningham]

thinking of a 12909 cutting out the flapper as im tuned. I dont want drone and not to loud cruising. i want it quiet enough to talk to someone without raising my voice.