Drone on new 2020s?

Jared Walters · May 7, 2020

Wanting to do a new muffler for the truck with new piping from muffler exit to tips. Thinking about the Corsa muffler that Aces Performance offers. Anybody got info on the drone with the AFM in the new trucks? Don’t matter what exhaust you have, just wondering if it’s to much to handle or just hold off and delete AFM first.

loud_pipes · May 10, 2020

2020 5.3L with 10 spd trans, Borla S Type catbacks and no drone. Flappers and screens eliminated. My 2015 5.3L with Flowmaster had a ton of drone. Muffler type will give different results, as will 5.3 vs. 6.2.

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Jared Walters · May 12, 2020

On 5/10/2020 at 5:29 PM, loud_pipes said:

2020 5.3L with 10 spd trans, Borla S Type catbacks and no drone. Flappers and screens eliminated. My 2015 5.3L with Flowmaster had a ton of drone. Muffler type will give different results, as will 5.3 vs. 6.2.

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Oh yeah I know different mufflers will determine different drone and stuff. On my 16, I swapped to Carven and obviously could tell when it dropped but it wasn’t TO bad.

INTJ · May 14, 2020

2020 6.2 Max Tow with GM performance intake and exhaust. No flappers, no drone. I can hear the exhaust when accelerating, but when cruising the exhaust noise is lost in the road noise.

RND4mGuy · May 27, 2020

Sorry I'm new to this. I know what a cat- back system is but what are "flappers" and "screens"?

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DirtyAndy · May 29, 2020

Oh yeah I know different mufflers will determine different drone and stuff. On my 16, I swapped to Carven and obviously could tell when it dropped but it wasn’t TO bad.

Progressive I assume. I had the Competitor series on my 18 and I had to buy a Range device. Lol

Jac365 · May 31, 2020

On 5/27/2020 at 12:27 AM, RND4mGuy said:

Sorry I'm new to this. I know what a cat- back system is but what are "flappers" and "screens"?

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If you look at the exhaust system you will see a flapper valve prior to the stock muffler on 5.3, and I believe one before and one after the muffler on the 6.2. Its a little restrictor that is inside the pipe. It opens to allow exhaust flow under acceleration, but closes back up as the RPM's come down. The screens are just that, sections of metal screen on the inside (towards spare tire) of both tail pipes. This is done to minimize drone. A cat back eliminates all of that stuff.

I put a Borla S type cat back on mine, Very happy with it.

Edited May 31, 2020 by Jac365
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DirtyAndy · May 31, 2020

If you look at the exhaust system you will see a flapper valve prior to the stock muffler on 5.3, and I believe one before and one after the muffler on the 6.2. Its a little restrictor that is inside the pipe. It opens to allow exhaust flow under acceleration, but closes back up as the RPM's come down. The screens are just that, sections of metal screen on the inside (towards spare tire) of both tail pipes. This is done to minimize drone. A cat back eliminates all of that stuff.

I put a Borla S type cat back on mine, Very happy with it.

What truck do you have? Any drone? What about when the truck goes to V4 mode?

On my 18 with Carven Competitor, V4 sounded like absolute garbage and I used the Range AFM religiously.

Jac365 · May 31, 2020

I have a 19 AT4 5.3. Prior to this I had a 12 Sierra SLT 5.3 with AFM. I also used the range box on my 12. I hated the V-4 mode.

As of right now I do not have a Range box for the AT4, but I do plan on getting one. If you REALLY listen for it you will hear subtle differences in the exhaust tone with the Borla. These new trucks also have a decal burble as they downshift, much the same as my old tweaked 5 speed stick IROC Camaro did when downshifting. Nice little rumble.

Under acceleration you WILL hear the Borla in the cab. Cruising along you will not, the road noise will be louder. These new trucks have DFM, which is different from AFM. With AFM the SAME 4 cylinders are deactivated every time. With DFM ANY cylinder can be activated or deactivated. It may run with 2,3,4,5,6,7, or all eight cylinders, depending on what power is needed. From what I understand running the Air Conditioner will keep all 8 cylinders activated.

I am not a fan of any cylinders being deactivated. I bought a V-8 because I WANT a V-8. I don't give a rats ass about MPG. But Federal regulations are forcing the manufacturer to come up with ways to attain mandated ratings.

Does the truck sound as good as my old 2004 Pro Sport Sierra with the 5.3 and the Corsa duals and no AFM/DFM? Almost, which is good enough for me.

And if you used a Range Box, your truck should NEVER go into V-4 mode.

Edited May 31, 2020 by Jac365

DirtyAndy · June 1, 2020

Hell, I can hear subtle differences in the DFM with the stock exhaust. I wasn’t planning on putting exhaust on my 2020 AT4 for this reason. I feel like it would amplify it more than I want.

beefin06 · June 2, 2020

On 5/31/2020 at 9:09 AM, Jac365 said:

From what I understand running the Air Conditioner will keep all 8 cylinders activated.

Is this true?! Is it really that simple?

Jac365 · June 2, 2020

3 hours ago, beefin06 said:

Is this true?! Is it really that simple?

If it ever warms up enough here in the northeast to use the air conditioner I'll be able to find out for sure.

DirtyAndy · June 3, 2020

No. I can tell when mine cuts out with my AC on. My 2018 was the same way.

Jared Walters · November 15, 2020

On 5/10/2020 at 5:29 PM, loud_pipes said:

2020 5.3L with 10 spd trans, Borla S Type catbacks and no drone. Flappers and screens eliminated. My 2015 5.3L with Flowmaster had a ton of drone. Muffler type will give different results, as will 5.3 vs. 6.2.

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My plan is to just replace the muffler with a Corsa muffler a local shop sales. Either that, Borla, or back to Carven like I had on my 16. I'm going to get rid of the flapper valve and I THINK just have all new piping ran from the muffler back to corsa style tips so I can get rid of the mesh screens without having to try and cover them. I'm hoping the drone wont be to bad, I've just read where the screens take away from some of the actual exhaust sound.

t-bone · November 15, 2020

My 2021 Trail Boss w/6.2 and 10 speed shows up in 2 weeks. Have done a lot of searching and I think I got it. Delete boths valves and replace stock muffler with Flowmaster 3.5" 40 series for max flow and run tranny locked in 9th to eliminate ugly AFM noise. Hoping that running cold air intake and 3.5 " pipe all the way back makes the same power as GM power package, 435 HP . Also hoping FM muffler and leaving resonators in place keeps drone at bay while holding 9th gear eliminates AFM. Sound like a winner?