[Dvs510]

Don’t want to mess with my warranty so instead of removing I was gonna gut the secondaries so it still appears they r there to the dealership.. anybody done this yet and if so any noticeable sound change? And how exactly did u do it?

[KingLT1]

Secondary cat removal doesn't void warranty.

[Dvs510]

Originally Posted by KingLT1

Secondary cat removal doesn't void warranty.

That’s what I originally thought until a mechanic at Chevy said don’t take them off like everyone is doing because it will void the warranty. And then also a couple people I have asked said same thing. I know it’s not required in Cali for smog but the warranty is what I’m sceptical about at this point. So I figured I would hollow them out so it atleast looks like they’re there for the dealership

[lokitwitch04]

Take off the entire catback, cut a square notch out of the top and gut them. Then weld the notch back in. That's what I did. I gutted both cats but wanted it to look factory. you cannot just knock them out like the primary cats. Trust me I tried. I'm sure the pic is upside down but you get the idea.

[KingLT1]

Originally Posted by Dvs510

That’s what I originally thought until a mechanic at Chevy said don’t take them off like everyone is doing because it will void the warranty. And then also a couple people I have asked said same thing. I know it’s not required in Cali for smog but the warranty is what I’m sceptical about at this point. So I figured I would hollow them out so it atleast looks like they’re there for the dealership

I don't know how it can void the warranty, they are apart of the cat back exhaust and are not monitored by the ECU therefor it shouldn't matter. However, You can talk to 100 different dealers and get 100 different answers.

[Laststandard]

Originally Posted by KingLT1

I don't know how it can void the warranty, they are apart of the cat back exhaust and are not monitored by the ECU therefor it shouldn't matter. However, You can talk to 100 different dealers and get 100 different answers.

Yup, all up to the dealer.

It is part of the emission control system so removing / altering gives the dealer a reason to deny warranty for emissions or exhaust related issues.

[FrostySS]

I guess in theory it could ruin the warranty on the exhaust but that's a huge huge huge stretch. Otherwise anything else warranty wise it's not affected....at all....period.

[Dvs510]

Originally Posted by lokitwitch04

Take off the entire catback, cut a square notch out of the top and gut them. Then weld the notch back in. That's what I did. I gutted both cats but wanted it to look factory. you cannot just knock them out like the primary cats. Trust me I tried. I'm sure the pic is upside down but you get the idea.

Thank u. U just saved me from wasting my time thinking I could just knock it out. Now I can prep myself knowing that’s what I need to do... was there any noticeable sound difference? Also, is it necessary to cut that big of access or can I make a smaller opening just on top side?

[Dvs510]

Originally Posted by KingLT1

I don't know how it can void the warranty, they are apart of the cat back exhaust and are not monitored by the ECU therefor it shouldn't matter. However, You can talk to 100 different dealers and get 100 different answers.

Yea I totally agree with u.. for that reason that I can’t get a consistent answer or something on paper stating.... I’d rather just not take the chance and take the extra effort to gut them and put back on

[24v]

Originally Posted by Dvs510

That’s what I originally thought until a mechanic at Chevy said don’t take them off like everyone is doing because it will void the warranty. And then also a couple people I have asked said same thing. I know it’s not required in Cali for smog but the warranty is what I’m sceptical about at this point. So I figured I would hollow them out so it atleast looks like they’re there for the dealership

The rear cats are definitely required for smog in California. It is just that many places don't know, or care enough to look for them as they will not set a check engine light if removed.

As for warranty issues, that is best to check with who ever does your warranty work. There are tons of people on the internet who will tell you that there is no way they can deny warranty for that, etc. The fact of the matter is that by removing, or gutting, the secondary cats you are tampering with the emissions system which is against Federal and State law, and I would bet there is also wording in your warranty about doing such.

BTW, I'm not saying don't do it, I love mods like anyone else. Just wanted to share some facts.

[FrostySS]

They can't void his entire warranty for removing the secondary cats. I'm a former GM service manager, unless the dealership had a giant bug up their ass they wouldn't care and at worst they'd refuse to exhaust warranty work. The rest of his warranty(bumper to bumper and powertrain) is irrelevant to the secondary cats

I didn't realize he was in California, that's the specific state they're on there for so he's technically ****ed there lol

[6spdhyperblue]

Dont breathe that shit. Not worth it. Either cut em off or don’t.

Get a axleback

[24v]

Originally Posted by FrostySS

They can't void his entire warranty for removing the secondary cats. I'm a former GM service manager, unless the dealership had a giant bug up their ass they wouldn't care and at worst they'd refuse to exhaust warranty work. The rest of his warranty(bumper to bumper and powertrain) is irrelevant to the secondary cats

I didn't realize he was in California, that's the specific state they're on there for so he's technically ****ed there lol

I never said anything about voiding his warranty.

[KingLT1]

You could do a cat back and get the borla X pipe that has resonators. they are basically the same thing as the factory secondaries units because they are not monitored by the ECU. AGAIN, You can't claim a part as emission compliant if the ECU doesn't monitor it. GM never intended for these to be a part of the emissions system, they were stuck in place to keep California happy.