97-01 Catalytic Converters prone to failure too?

[mikejwil]

My 93 XJ had the good ol' rattling cat back in the day, so I replaced it when I did the muffler. I now have a 99 XJ w/95K miles with a rusted out muffler which I will be replacing soon. My cat is not rattling even if I whack it with a mallet...so I think it is prolly still good. It does have quite a bit of exterior rust though. Are the 97+ cats prone to failure like the old ones were? It is a different design (round instead of oval), so maybe the issue was resolved? Just wondering if I should go ahead and do it when I do the muffler.

Thanks.

[Ronbo]

My 98 has 140k on the original cat and it still passes Cali smog testing. But rust isn't a factor on this one.

[Michaelarchangelo]

I have a 98 that has rusted fairly bad on the outside, but I haven't noticed any problems (i.e. clogged) and I have 168k. I might go wack it later on to see if it makes any sounds.

[fender]

190K+ with no problems. I found a crack in the header and the clamp to the muffler has disentergrated... I think i am going to replace the whole thing soon including the cat just to get it done once and done right. I hate working on exhaust systems....

[dyna]

Supposedly when the manifold cracks it allows air to enter the system then passing the O2 sensor and telling its lean, the comp then richens the mixture a little and the cat gets overheated burning the xtra fuel.