[Drateryako]

So i just recently bought a 2018 Camaro SS. The previous owner had LT headers and an aftermarket exhaust put on. There were no cats underneath at all and I live in an area with emissions testing so I figured I would get some put on, also wanted to get rid of some of the rasp.

Had a shop install high flow cats and not even a month later I could hear rattling inside the exhaust. Had it brought to my dealer and they confirmed that the right side cat was breaking up inside.

I'm going to the exhaust shop on monday to get it replaced since it is warrantied, what I want to figure out is when they get the cat cut out if it will be obvious what exactly caused it to go bad.

I don't know if I just got unlucky and got a defective cat or if its something else.

I'm pretty positive the previous owner had the vehicle tuned. Could that tune be a reason that the cat went bad so fast?

The only other reason I can think of is I hit a speed bump really hard at night about a week prior to hearing the noise, it basically had no paint on it and didn't see it until I was too close to slow down, maybe the speed and force on impact messed up the cat?

I know I threw a lot of random information out there, but like I said with the 3 reasons I gave is there anyway to tell which one it might be once they get the old cat cut out?

Thanks

[cjperformance]

What type of cat? You say high flow, but is that OEM replacement type, or like kooks cats?

[pauly1119]

Yes when it’s removed you can see it but it also can be from the old cats removed. Where they hollowed out or completely removed? The material the cats are made of is pretty tough stuff and is hard to come apart. I hollowed out a set on a Corvette, took some work.

[Drateryako]

i dont know the exact model of them. they are not oem cats, they are some universal 3" cat.

[Drateryako]

Originally Posted by pauly1119

Yes when it’s removed you can see it but it also can be from the old cats removed. Where they hollowed out or completely removed? The material the cats are made of is pretty tough stuff and is hard to come apart. I hollowed out a set on a Corvette, took some work.

There was no cats at all when I got the vehicle. I know i will be able to see the damage when they are taken out, but will I or someone with more knowledge be able to determine from looking at it what exactly caused the damage?

[pauly1119]

Originally Posted by Drateryako

There was no cats at all when I got the vehicle. I know i will be able to see the damage when they are taken out, but will I or someone with more knowledge be able to determine from looking at it what exactly caused the damage?

If the exhaust hit the ground I don’t think it would cause it to come apart, a bad tune or the car running too rich can cause early failure, but I would think this would take some time. It also could have been there from the old exhaust and moved. Maybe ask the shop to remove the whole exhaust and make sure there isn’t anything else in there. Parts can get caught in the muffler too. It really isn’t a big job especially for an exhaust shop and then you’ll know it’s all clear.

[m6-lt1]

I’m going to assume these weren’t name brand cats like kooks or arh being used. To be honest most of those “replacement” type aftermarket cats are not nearly as robust as oem. If you haven’t already smoged your car you may have trouble passing. But these aftermarket cats do have a high failure rate. You should honestly try to buy used oem or new oem.