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Catalytic Converter - Replace entire Y piece?

chaddlyd

Full Member
Joined
May 27, 2009
Messages
18
Location
Kentucky
I am seeking some answers/opinions, which I know you guys have a lot of!!!

My catalytic converter on the driver's side is shot.  It rattled loudly for a couple of weeks and now doesn't make much noise at all.  I made sure that this was not an o2 sensor by removing the sensor and giving the pipe a good tap with a rubber mallet.  It is also not the heat shield.  The rattle was definitely in the Cat.  I am now getting the dreaded service engine light and the code is for Cat. 

What would you guys do?  Replace the entire Y assembly (aftermarket  or OEM)?  Have a muffler shop just weld in a new cat in the driver's side? 

I was quoted around $180 to just replace the cat and have the shop weld in a new one.  The other option is to get under the truck and replace the whole thing DIY style (both Cats at once) for anywhere between around $300-450 depending on brand.

Any comments/answers/suggestions are much appreciated.  Thanks in advance!
 
Replace both cats. Do not replace just the drivers side. Also you should probably replace the O2 sensors while your at it to avoid any unwanted headaches later.

I replaced both of my cats with a magnaflow Y pipe at around 130k miles. I would suggest doing the same. I am assuming you are up there in mileage and the cats simply went bad, meaning they slowly got clogged and melted.

Also dot forget to sell those bad cats. They still have precious metals in them and are worth more than just scrap metal.
 
Yup.  I am at 124K and also have a cat-back Magnaflow system, so it looks like that's what it'll be.  Not a bad idea on the o2 sensors either.  I just ordered both front wheel hub bearing assemblies as well.  Looks like I've got some work to do!  Oh well, it's all part of it...  thanks for your 2 cents. (y)
 
butterfingarz said:
Replace both cats. Do not replace just the drivers side. Also you should probably replace the O2 sensors while your at it to avoid any unwanted headaches later.

I replaced both of my cats with a magnaflow Y pipe at around 130k miles. I would suggest doing the same. I am assuming you are up there in mileage and the cats simply went bad, meaning they slowly got clogged and melted.

Also dot forget to sell those bad cats. They still have precious metals in them and are worth more than just scrap metal.
Would you still happen to know that part number?
 
Found an ebay seller selling one for $368 + Free Shipping.  It has already reached my doorstep!  I'm in KY, so no CA cats required here.  As a matter of fact, we don't even have emissions inspections here.  I could've gotten by with some other modifications, but didn't fell like messing with it.  I hope it's not too much of a PITA to get the old one out!
 
chaddlyd said:
Yup.  I am at 124K and also have a cat-back Magnaflow system, so it looks like that's what it'll be.  Not a bad idea on the o2 sensors either.  I just ordered both front wheel hub bearing assemblies as well.  Looks like I've got some work to do!  Oh well, it's all part of it...  thanks for your 2 cents. (y)

I just had both cats replaced 03 z71 101k, the shop didn't replace the o2 sensors. The Avy ran like a champ for a week or two. Now its bogging on acceleration. No codes. Also when I romp on the gas the thing acts like the trans doesn't know which gear it wants to go into. I was just browsing around here and got to thinking...could my 02 sensors be causing my probs? As I mentioned, no codes. I've replaced the plugs, new k&n, cleaned MAF, and throttle body, i always run good gas, ive run lucas injector cleaner through it on a few tanks. I'm stumped.  My other thought was, I saw theres a software update for the PCM, not sure if mine is included in this. Any ideas? Could my o2's be the culprit?
 
You should always replace the O2 sensors when replacing the cats. The O2 sensors could have been the culprit the cats went bad in the first place but I doubt it since you have on 03 and over 100k. I believe you can have the O2 sensors checked by some shops or put an ohm meter on them but sounds like you already knew what the culprit of your issues are.
 
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