[PatMcGrath]

Hey guys, I'm new to the forum but already in a bit of a troublesome situation. I own a 2001 Nissan Xterra XE, 5 spd standard, and recently my exhaust rotted out from under me. So I ordered up a y pipe and muffler from Bosal, ready to bolt up. Last night I got underneath my Xterra, cut off the bolts holding the y-pipe in, and thats where everything went wrong. After removing the section of exhaust I had intended to replace, I noticed that the flanges coming back from the Cats were to corroded to bolt up to. So, not a problem I figured, I started to cut the pipe with the intention of sleeving that bit of pipe and putting a flange on it, so that I could bolt my new y-pipe to it. However, in the process of cutting the pipe, my Cat fell right out. The studs that connect the back cat to the front cat on the drivers side were so rusted that the vibration caused the back cat to rip free of the studs. I've never even seen this happen before. I'm living on the east coast of Canada though, not originally from here, and not used to the corrosive effects of the ocean.
In any case, my question is, has anybody run into a problem like this? I'm wondering if I have to completely remove all four cats, and either order new ones, or if I can drill out the studs. Frankly, I'm worried with how corroded they are, if I'll even be able to disconnect them from the exhaust manifolds without stripping bolts and having to vise grip half them out.
The two cats seem to be held together with studs rather than nuts, can anyone confirm this? In any case, I'm in a world of trouble trying to get this apart, and the best price I can find if I have to replace 4 cats is about $300 a pop online.
Any tips would be appreciated.

 

[TJTJ]

I don't know Canada's regs on emissions, but, in parts of the US, except for California for example, you can sometimes legally run just the first two cats and be fine.

 

[xtacular]

Yeah it comes down to how and what they inspect. Is it a sniff test, visual inspection, or just checking to see if the MIL works and is off? If it's anything but a sniff test, you can get some cheapy Magnaflow cats.