Magnafliw 12909 on 6.2

[michigan2500hd]

So I ordered the stainless 12909 Magnaflow muffler and stopped by a shop to get a estimate on installing it. Told him I wasn't to keep the flapper valve. There doesn't seem to be many in here that just swap out the muffler and keep the valve.

This issue in keeping the valve is that the exhaust necks down to 3" at the valve so a adapter is needed. Now to find a 3.5" to 3" stainless adapter. Hopefully this week or next my truck will finally sound like it should.

 

Sent from my SM-N950U using Tapatalk

[Black02Silverado]

A good exhaust shop can adapt that muffler to fit with no problem. No need to find an adapter.

[RUSSH]

My muffler shop had no issues installing mine.

[michigan2500hd]

No need for adapter if they have the correct size expander right ? These guys didn't have it which is a bummer because they had great customer service as only wanted 50 bucks to install if I supplied the adapter. Dang I'm getting Impatient

 

Sent from my SM-N950U using Tapatalk

[Iceman22]

Funny you posted this as I was just searching for previous threads about the 12909 on a 6.2L

 

It seems like most guys opt to delete the factory muffler and flapper but retain the resonator further back....I will soon be getting a BBP tune so I'm not worried about the v4 chop. Can any of you with this setup comment on how much it drones?

 

I essentially am looking for a setup that's throaty on cold starts and sounds aggressive when really leaning into it but at the same time is quite at cruising speeds. Do you guys think that describes the 12909?

 

Also, it's great to hear ballpark pricing on what this cost to install!

 

 

Sent from my iPhone using Tapatalk

[Fishbait]

I cut off the flapper valve and I have zero drone on mine.

 

Sent from my SAMSUNG-SM-G920A using Tapatalk

I also left the resonator on.

 

Sent from my SAMSUNG-SM-G920A using Tapatalk

[2014KL]

For those who kept the resonator and cut off the flapper did you tune out the afm? If not does it give that horrible wawawa noise in 4 cylinder mode? I'm thinking about going with the 12909 and not sure if I should keep the flapper.

[Fishbait]

For those who kept the resonator and cut off the flapper did you tune out the afm? If not does it give that horrible wawawa noise in 4 cylinder mode? I'm thinking about going with the 12909 and not sure if I should keep the flapper.

No flapper and no wa wa wa sound here. You can always keep the flapper on and wire it open.

 

Sent from my SAMSUNG-SM-G920A using Tapatalk

[Chad2815]

No flapper here no drone, I actually think its not as loud when cruizing but louder when its wide open.

[Lgetz]

Magnaflow 12909 as well with no flapper either but retained resonator. Slight V4 chop and no drone. Competent muffler shop will be able to install muffler without issue flapper or not.

[country_09]

12909 on mine as well...I can't speak for the drone or v4 mode as I went with LTs and no cats right off the bat. I did delete the flapper and the rear resonator and dumped it over the axle with a 5" tip. I love the way it sounds. Great muffler choice for the 6.2

[mayfieldjeff]

i plan on getting a 12909 as well after reading all the comments. i just want a little louder at start up and WOT but like stock at cruising as we take my truck on all the vacations.

i also plan on getting the aFe CAI. I'm hoping the combination of the two will get me at least 1-2 MPG...

[michigan2500hd]

I'm having a beck of a gone finding a shop in Michigan that can expand to 3.5" pipe. All because I want to retain the flapper valve. Heck some shops don't even know what it is..one told me today it was a heat riser lol.

I always run into issues like this.

 

Sent from my SM-N950U using Tapatalk

[RUSSH]

Funny you posted this as I was just searching for previous threads about the 12909 on a 6.2L

 

It seems like most guys opt to delete the factory muffler and flapper but retain the resonator further back....I will soon be getting a BBP tune so I'm not worried about the v4 chop. Can any of you with this setup comment on how much it drones?

 

I essentially am looking for a setup that's throaty on cold starts and sounds aggressive when really leaning into it but at the same time is quite at cruising speeds. Do you guys think that describes the 12909?

 

 

 

No drone from mine and yes, that is a perfect way to describe this muffler.

For those who kept the resonator and cut off the flapper did you tune out the afm? If not does it give that horrible wawawa noise in 4 cylinder mode?

No.

[michigan2500hd]

Magnaflow 12909 as well with no flapper either but retained resonator. Slight V4 chop and no drone. Competent muffler shop will be able to install muffler without issue flapper or not.

Shoot I can hear slight v4 chop with the stock system at times. I'm sure that I'll hear it more with any aftermarket muffler.

I don't just hear it in my truck either.. is about every '14 and newer that I've driven. Of course I'm always listening to whatever I'm driving... and I'm strange.

 

Sent from my SM-N950U using Tapatalk