[Silent_H_]

I'm posting this here instead of in the V6-specific forum as I think it's probably pretty universal.

My car recently started making a loud rattle near 3k and 5k rpms. None of the heat shields on the exhaust were making noise when I got under there, so I took it to the dealer.

They said that the welds on a pipe in the resonator are coming loose, and quoted me ~$4000 to replace the entire exhaust from the cats back.

That seems a bit steep to me, so I was wondering if anyone else has had a similar issue, and what you did to solve it. Can an exhaust shop try to fix the broken weld? Can they cut out the resonator and replace it with an x-pipe or something?

I really like the sound of the factory exhaust, and don't want anything that drones. I did look into 3rd party ones, but for the V6 I could only find axle-back, so they wouldn't solve my problem.

Thanks!

[RIPws6]

Originally Posted by Silent_H_

I'm posting this here instead of in the V6-specific forum as I think it's probably pretty universal.

My car recently started making a loud rattle near 3k and 5k rpms. None of the heat shields on the exhaust were making noise when I got under there, so I took it to the dealer.

They said that the welds on a pipe in the resonator are coming loose, and quoted me ~$4000 to replace the entire exhaust from the cats back.

That seems a bit steep to me, so I was wondering if anyone else has had a similar issue, and what you did to solve it. Can an exhaust shop try to fix the broken weld? Can they cut out the resonator and replace it with an x-pipe or something?

I really like the sound of the factory exhaust, and don't want anything that drones. I did look into 3rd party ones, but for the V6 I could only find axle-back, so they wouldn't solve my problem.

Thanks!

That seems pretty steep! Get quotes from other places for the same work.
You might even have another outfit look at it.
You can buy a high performance exhaust and install it for less than that. Doesn’t sound right at all to me.

[TooleyOnDeck]

I don't think NPP exhaust has a resonator, maybe the V6 is different?

Either way, any exhaust shop should be able to replace or delete a resonator pretty easily, but if you wanted to replace the whole system, here is a complete NPP for $800: https://www.ebay.com/itm/38684230169...BoCuloQAvD_BwE

[Silent_H_]

Thanks!

[arpad_m]

There are pipes, chambers and welds inside the big NPP muffler, see below. Although rare, it's possible that you'd get vibrations and rattles from defective muffler internals.

[JT6Speed]

Originally Posted by arpad_m

There are pipes, chambers and welds inside the big NPP muffler, see below. Although rare, it's possible that you'd get vibrations and rattles from defective muffler internals.

Do you know if that empty space usually contains packing of some sort (and was removed for clarity)?

[Kamero6]

Originally Posted by Silent_H_

I'm posting this here instead of in the V6-specific forum as I think it's probably pretty universal.

My car recently started making a loud rattle near 3k and 5k rpms. None of the heat shields on the exhaust were making noise when I got under there, so I took it to the dealer.

They said that the welds on a pipe in the resonator are coming loose, and quoted me ~$4000 to replace the entire exhaust from the cats back.

That seems a bit steep to me, so I was wondering if anyone else has had a similar issue, and what you did to solve it. Can an exhaust shop try to fix the broken weld? Can they cut out the resonator and replace it with an x-pipe or something?

I really like the sound of the factory exhaust, and don't want anything that drones. I did look into 3rd party ones, but for the V6 I could only find axle-back, so they wouldn't solve my problem.

Thanks!

NPP valves vibrate sometimes. I noticed it the most in Tour and stealth mode when they're closed.

[Bumbleboy92]

I’ve experienced the holy grails of exhaust rattles.

My 2016 v6 got both the AFM spring valves rattle and the resonator rattle. I replaced the resonator with a Jones X-Pipe I bought for $35 and shop installed for $100. Replaced the exhaust from the AFM valves to tips with a ZL1 stock NPP exhaust (from a manual so no AFM valves).

My 2022 SS had loose heat shield rattle which the dealership said they tightened the shields. Then also got the NPP valve squeak, I didn’t ask what they did but they fixed it. I keep the exhaust in Track 24/7 and on the v6 it was unplugged so the valves were always open

[The Maverick]

Originally Posted by JT6Speed

Do you know if that empty space usually contains packing of some sort (and was removed for clarity)?

This ZL1 video shows just a little bit, wrapped around the route to the "muffled" tail pipe, although the configuration of the pipes is also different than the cutaway: https://m.youtube.com/watch?v=_alMn3ha5MA

However, the following thread commenting on that 2015 cutaway exhibit says there is no packing:
https://www.camaro6.com/forums/showt...=427570&page=2

[arpad_m]

Originally Posted by JT6Speed

Do you know if that empty space usually contains packing of some sort (and was removed for clarity)?

Sorry, I don't. The design looks like it relies on pipe routing and perforation alone, though, so I would (naively) think no additional packing is used.

[JT6Speed]

Originally Posted by The Maverick

This ZL1 video shows just a little bit, wrapped around the route to the "muffled" tail pipe, although the configuration of the pipes is also different than the cutaway: https://m.youtube.com/watch?v=_alMn3ha5MA

However, the following thread commenting on that 2015 cutaway exhibit says there is no packing:
https://www.camaro6.com/forums/showt...=427570&page=2

Hey those are some good finds. Makes me wonder if the early designs had nothing in there and then maybe they added some small amount of packing.

Originally Posted by arpad_m

Sorry, I don't. The design looks like it relies on pipe routing and perforation alone, though, so I would (naively) think no additional packing is used.

I agree with what some people said in that old thread, in that some packing would have smoothed out the tone. Though I will say, after a couple of years it has gotten less bark to it, maybe because of buildup inside. Who knows.

[Silent_H_]

Originally Posted by Bumbleboy92

I’ve experienced the holy grails of exhaust rattles.

My 2016 v6 got both the AFM spring valves rattle and the resonator rattle. I replaced the resonator with a Jones X-Pipe I bought for $35 and shop installed for $100. Replaced the exhaust from the AFM valves to tips with a ZL1 stock NPP exhaust (from a manual so no AFM valves).

My 2022 SS had loose heat shield rattle which the dealership said they tightened the shields. Then also got the NPP valve squeak, I didn’t ask what they did but they fixed it. I keep the exhaust in Track 24/7 and on the v6 it was unplugged so the valves were always open

Thank you for linking the video and for the details. Mine sounds exactly like your resonator rattle, and the dealer said it was coming from the resonator.

When you replaced it with the X-Pipe, was it a ton louder or still about the same? I'm leaning towards going that route until something happens to the rest of the system.

[Bumbleboy92]

Originally Posted by Silent_H_

Thank you for linking the video and for the details. Mine sounds exactly like your resonator rattle, and the dealer said it was coming from the resonator.

When you replaced it with the X-Pipe, was it a ton louder or still about the same? I'm leaning towards going that route until something happens to the rest of the system.

It was very similar to original sound, maybe a tad bit more throaty but not anything I would notice if I didn’t know it was replaced

[Silent_H_]

Originally Posted by Bumbleboy92

It was very similar to original sound, maybe a tad bit more throaty but not anything I would notice if I didn’t know it was replaced

Perfect, thanks for the insight!!