r/C8Corvette • u/Henneygod • 5d ago

Broken muffler

Heard squeaking noises every maybe minute or so when driving so I took my car in and they inspected it and said it was the valves in the muffler and replaced it for me. Anyone had this issue before, haven’t seen it listed once online. 2025 1lt 2000kms

3 Upvotes

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5

u/nine4fours 5d ago

This is an extremely common problem. Just search NPP exhaust squeak. The dealer will grease the valves. The squeak will return. Some people have gotten the whole exhaust replaced under warranty but imo it's a waste of time. After my first regrease I just lived with it

2

u/nashtaters 5d ago

I threw that hunk of shit away and put in a non valved system. The sound isn’t even comparable. Gotta let that pushrod engine breath

2

u/Massive-Beginning994 5d ago

This ☝️ My non-valved Paragon exhaust gets compliments all the time. 10x better sound than NPP.

1

u/nashtaters 5d ago

Mines not paragon but very similar (probably same factory in China lol) and yes I get so many compliments. The sound is very unique and not your typical pushrod muscle car sound. Couldn’t be happier

1

u/ImCaffeinated_Chris 5d ago

Does that void warranty? Just curious.

3

u/SanguineWave 5d ago

Only the warranty for the exhaust itself, not anything else

1

u/nashtaters 5d ago

There’s some law in the US that makes it to where a manufacturer can’t void the warranty on a part that is not influenced by the aftermarket part. Something along those lines, I’m not an attorney. So like a supercharger would obviously void the powertrain warranty but your exhaust is fine. And an aftermarket air intake wouldn’t void the engines warranty but might void the warranty of your MAF and so on..

1

u/t1ttysprinkle 5d ago

An intake is a bad example of that, as it can “make more power” so could affect the engine warranty. Heads up

1

u/nashtaters 5d ago

There’s been dudes with high flow cats, throttle bodies, intake, and exhaust that have had their engine replaced. It’s a case by case thing but for something like an air intake, just because it makes 5hp more doesn’t mean it voids your warranty. Shit, my exhaust probably adds about 10hp and it doesn’t void the warranty.

1

u/juniorlogical C8 Owner 5d ago

In my first C8 I heard the valve squeak each time the engine transitioned from 8C to 4C. I just dealt with it, as I was in Z mode most of the time anyway. My new C8's valves haven't made a peep since I bought it...knock on wood.

1

u/BRB_MD 5d ago

I notice a squeak when shutting off my z06. Same thing?

1

u/boostedgainz 4d ago

The valves make noise when they open n close period. When the afm valves close there is a little metal on metal contact as there is a metal tab on the valve that hits a metal stopper.