I've got a few questions about replacing the cat myself rather than taking it to a shop.

What's the stock exhaust pipe size?

If the stock exhaust is 2", and I get a universal catalytic converter, which size input/output pipe will i need? And how do you clamp on a catalytic converter?

I got quoted by a shop around here for $200 to replace the cat. I'd like to try and do it myself and use that $200 for some other replacement, like the O2 sensors.

 

An OEM cat for my 95 pickup, 3.0 engine retails at over $900. I went with an aftermarket ($170) and it was about 1/3 the size of the one I replaced, it comes with a longer and adjustable pipe. Mine was easy to R&R, two nuts and bolts at each end and a clamp that came with the new cat. I soaked them for about three days with the home mix 50% acitone and 50% ATF.

If the $200 includes the cat, you won't save much by DIY.

I worry that I made a bad decision going with the aftermarket unit.

Harry

 

I think with my current cat, anything is better than what I have now. I see 2 kinds of cats: direct fit and universal. I'm looking at the universal magnaflow ones.

 

Magnaflow makes some pretty nice direct fit high flow cats. When i got mine 2 years ago it was $88 on ebay with free shipping. I took my old one to a scrap yard and got $150 for it lmao..fixed my exhaust leak and pocketd some cash! Theyre still on ebay but a little more money, mine had a part number of 23884 which is 105 shipped now. As long as you dont live in california you should be fine with the high flow. My truck actually is a cali emissions with an oxygen sensor after the cat and it did not trip a check engine light.

 

I cant use a direct fit. The previous owner sawed the old one off and looks like he welded a new one in place. So i don't have the fittings for the bolts for a direct fit cat.

 

I am currently trying to figure out if my cat is bad, I have failed the NOX portion of the california smog test. I have priced a few and if I need one will buy a magna flow direct fit for approx $185 at Kragens. Since some one has already butchered your pipes I would try and get some free advice from my local muffler shop as to what to do. Sounds like some welding may be involved

 

just buy a cheap cat and bring it to a shop and have them weld it in. A few weeks ago I picked up a walker cat from Advance for $70, it's a quality OEM replacement as far as I can tell.

 

I asked around, and most shops wont weld in an outside cat. has to be on from their inventory. Some BS about warranties or safety. I kind of agree. It's like bring your own steak to a resturaunt and asking the chef to cook it up without paying the $25 menu price/

 

any good exhaust shop will weld in a cat for you, it has nothing to do with warranties or safety, a catalytic converter is a catalytic converter, it's a pretty simple part, they just want to make money off you. I just had a local shop replace my downpipe and weld in a cat and an 02 sensor and bung that I brought in for $127 out the door. I guess if you want to pay more go ahead, I was just trying to help you save some money......

as to your steak analogy, if I brought my own steak would I be paying the chef to cook it (i.e. for his labor) or would I just be expecting I can sit down in his restauraunt and have him cook me a steak for free? Either way what you said about steaks makes no sense because that would never happen. On the other hand a good exhaust shop welding in a cat for someone for a fee is something that is very likely to happen and in my case and I'm sure many others has happened. At any rate I hope you get it worked out. Some people just like to pay more for things I guess.

 

Check your EGR system

 

you can go to an auto zone and they will scan your computer for free and can tell you if its your cat or your o2 sensor