6.2L exhaust - Magnaflow, Flowmaster, other?

therapy · February 7, 2017

On my 5.3L 2007 Sierra I had a Magnaflow exhaust and loved it - low rumble on cold starts and at low speeds - seemingly disappeared at highway speeds.

I'm looking for something the same - I want to hear it start up, I want to hear it at low speed (accelerating from stoplights, etc) but I don't really want to hear any highway drone.

I have a 2014 6.2L High Country (CCSB), does anybody have some suggestions?

emeryz28 · February 7, 2017

huge debate about this. I want to do my exhaust but cannot make a decision. I know the Corsa sounds awesome but I don't want to drop $1200. The MBRP is often described as too loud, Magnaflow as too quiet....

Lots of 6.2 guys have just don a muffler delete and says it sounds great, I am thinking about doing that.

drentlaw1 · February 7, 2017

I have the Corsa sport cat-back on my 6.2 and love it. Very nice rumble with start up and idling. Gets pretty loud when you floor it, but cruise set at 80- 85 MPH no drone and quiet. For me its not loud enough and plan on doing long tubes next! It was hard shelling out the $1200 but i spent HOURS watching youtube videos and liked the sound of the Corsa best.

wuznme · February 8, 2017

I have a slightly used Magnaflow in FS section...

Silver ice 6.2 · February 8, 2017

Go with borla.

SkiDooNick700 · February 8, 2017

I'm not trying to derail the thread, but Corsa does have the db Series which is like half the cost of the Corsa, however they only make it for the 5.3L and therefore piping is 3inch instead of 3.5.

What kind of impact would that have? It sure would be nice to have the db Series as an option for us 6.2L guys.

GMC_SD_Ult_16 · February 8, 2017

I removed muffler, flapper, and resonator and put in a Magnaflow 12909 22" with 3.5 inch in and out for my 6.2L....I am happy overall... Very little drone compared to muffler delete (please note there is not much drone with muffler delete if you leave flapper in place but my flapper started making strange sounds - not all do but many persons on the forum did not have good luck with sound after muffler delete with flapper). Magnaflow has good low rumble in start, low drone Hwy and 30-40mph cruising, and great sound when giving it the gas. Some think it is too quiet but I wanted a full 3.5 inch in/out and made my choice with what was available.

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therapy · February 8, 2017

Forgive my ignorance, but what are the "flapper" and the "resonator"?

Lgetz · February 8, 2017

The "flapper" is a piece directly behind your muffler that contains a valve which is closed at low speed or part throttle to reduce exhaust droan. The resonator is a secondary muffler located on the tailpipe before it exits the rear also to reduce exhaust drone.

Lgetz · February 8, 2017

I removed muffler, flapper, and resonator and put in a Magnaflow 12909 22" with 3.5 inch in and out for my 6.2L....I am happy overall... Very little drone compared to muffler delete (please note there is not much drone with muffler delete if you leave flapper in place but my flapper started making strange sounds - not all do but many persons on the forum did not have good luck with sound after muffler delete with flapper). Magnaflow has good low rumble in start, low drone Hwy and 30-40mph cruising, and great sound when giving it the gas. Some think it is too quiet but I wanted a full 3.5 inch in/out and made my choice with what was available.

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Did the exact same mod with Magnaflow 12909 except kept the resonator in place and am very pleased. Suggest those with a 6.2 try this before dropping big money on a cat back. Some are not happy with the lack of noise but that can be remedied by removing the resonator. Add a nice stainless steel tip and you should not be into this mod for more than $350.

Luster · February 8, 2017

Magnaflow is a "filled" muffler design. It has steel mesh and fiberglass interior fill to absorb exhaust sound, but still lets the deep tones through while absorbing drone.

Flowmaster is a "chambered" design. It cuts very little of the sound level and volume, but removes some of the raspiness of a muffler delete. Flowmaster mufflers tend to drone more than Magnaflow.

country_09 · February 8, 2017

Another for the magnaflow 12909 on my 14 6.2. Love it. Sounds perfect

emeryz28 · February 8, 2017

so if you cut out the stock muffler and flapper, the 12909 fits right in there?

GMC_SD_Ult_16 · February 8, 2017

so if you cut out the stock muffler and flapper, the 12909 fits right in there?

Yes.. It is an offset muffler with a total length of 28" (including the pipe inlets and outlets - muffler portion is 22") so you will need someone that can bend 3.5" pipe to get it to line up with existing 3.5"... Also on my 6.2L the size of pipe after the OEM muffler went back and forth between 3" and 3.5". Since I had them remove the resonator and flapper I went ahead and had 3.5" pipe added all the way to back then added twin stainless corsa style tips exiting on the passenger side.

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Lgetz · February 8, 2017

so if you cut out the stock muffler and flapper, the 12909 fits right in there?

Absolutely. Shop I used measured things just right and cut the muffler and flapper off precisely and MIG welded the new muffler in place with no piece of 3.5 inch pipe needed. I will snap a picture in a bit and post.