The old pieces ('98) are slip fit/clamp on. Only place old exhaust is welded is tailpipe to muff.

 

So I should just be able to knock it free with a hammer?
Since it's been on there for 13 years I'm thinking that it has possibly "melded" itself on with all the heat.
Will hammering it out put stress on the front pipe or headers and cause a crack?

 

My exhaust from the muffler back fell off when I kicked it while installing my leaf springs.

A hammer will be more than enough.

 

you live in an area with less rust...

 

I'd be real careful with a hammer for fear of placing a strain on the pipe and manifold ahead of the cat. Shoot some penetrating oil in the slip fit joint, remove clamp and try a twisting motion while pulling back. Me thinks the muff/tailpipe should come off 1st, then the cat, then slip on new cat, then new muff.

 

Great I'll take some before and after pics and document any pitfalls I encounter.

 

Nope. Not true.

Have you ever tried running your truck without the cat? Have you ever tried doing so without unplugging your rear o2 sensor?

I know the CEL won't get tripped unless the rear o2 sensor is removed completely.

Someone who posted in this thread knows it too.

Now, is it legal?

No.

Is it good?

No.

 

See post #8.

 

Wonder who I was talking about...

 

.....3 guesses and the 1st 2 don't count. Bingo, he wins a rubber dolly. But hey, at least I was being stealthy about it. Probably toast now.

 

I have a '94 with no cat sensor, doesnt through a code.
nether does my brothers '97
or dads '96 wrongler

 

No O2(s) and no CEL/codes???????? Didn't think OBD-I had an after cat O2.

 

my bad.

 

Sorry to hijack here but could someone tell me why my 91 has no o2 sensor after the cat, only on the downpipe? I thought renix ended in 90 and only had one on the downpipe.

 

obd2 has one down stream to see if the cat is functioning properly