Hi all,
2001 xj, 210k miles. stock.

I replaced the muffler 6 months ago with a walker muffler from rockauto. Today I replaced the original cat with a walker cat from rockauto.

2001 has mating flanges so muffler and cat can be swapped out without any welding. Nice.

Here's my 4 issues:

1. My new walker cat doesn't seem to fully lock in place where the cat meets the muffler (see pic). I can try to crank down harder on the two bolts but it feels snug. Not sure how much harder to crank down or if i'll mess up the threads.

2. The noise is way different: lower rumble. It is a pretty big difference in sound. Anyone experience that?

3. I forgot to get a gasket between the cat and the header pipe--do I need one?

4. Do I need to reset my computer after this?

 

Yes you need that gasket in between the header and the rest of the piping