2021 Camaro 1LE Rattle
I have a 2021 Camaro 2SS 1LE with a Manual Transmission. The car has 8k miles on it and runs great, EXCEPT for an inconsistent rattle that overpowers the whole car. It's not just some slight interior rattle, (because believe me.. it comes stock with plenty of those). This rattle itself overpowers the engine, exhaust, and can even be heard with the windows down.
The car has an aftermarket axleback exhaust the original owner put on it. I've had it at 2 different shops trying to figure it out. One shop put a bunch of dynamat material around all sorts of plastic interior trim which accomplished nothing. I had another shop estimate that the axleback tips of the exhaust were striking the bumper so they lowered the exhaust slightly to make sure that contact wouldn't be possible. After all this and a bunch of money spent, the rattle is still the same.
It's most pronounced after driving the car really aggressively and can be head on acceleration, deceleration, and most pronounced in 5th-6th gear when the engine is bogged down (which I don't do too often, but it's a good way to make the noise come out).
I've had a couple people suggest maybe the rear window wasn't mounted right at the factory and maybe that's the noise? Also I can't get the noise to come out reving the car in neutral either.
I'm so lost and am open for any ideas. Attached is a video to show you the noise:
Thanks for reading!
The vehicle is so new I would take it to the dealership and make them fix it under warranty.
Have you tried the 'cheap' route of having a passenger in the car when the noise appears? That may help pinpoint where it's coming from.
I've done that before and have had success. As long as it's in a safe situation, your passenger may be able to move around a bit and find it.
I can't help but to wonder if going back to the stock mufflers would cure it. That axle back set up sounds like it has a lot of resonance and drone.
@jpparisio I'm scared of going to a dealer because they will probably just blame it on the aftermarket AWE Axleback Exhaust on it and not even try to help with anything.
@autodiy I've been in the back seat as it has done it and I just kept thinking it was some plastic interior panel. The first shop had 2 employees test drive it with someone in the back and they agree'd with me.... but despite that we couldn't fix it.
The second mechanic told me, despite lowering the exhuast... he told me he didn't think it would ever be 100% perfect because the way this axle back is setup, he thinks the resonance is just quite a bit with no mufflers on it. Unfortunately, I bought this car used and the stock mufflers aren't around at all.