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Catalytic Converter Question

jrb21284

By jrb21284
in Ask A GM Technician

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jrb21284 Enthusiast

jrb21284

Posted
Posted

I am in need to replace my catalytic converters on my 98 GMC z71 5.7L short bed, But from what my local shop is telling me is that its not advised that i cut the old ones out and replace them, but to buy the whole setup, which looks something like this:

 

652045.jpg

 

My question is can I just replace the converters or do i have to replace the whole setup? and where can i get a decent deal on this?

citydriver Enthusiast

citydriver

Posted
Posted

Replacing the converters is possible but may be more expensive with parts and labor to have them welded in. Not to mention making sure the welds are done right. New converter assemblies are may be the way to go and are easier to install and usually come w/ a warantee. Yopu can get them from Summit Racing as well as other retailers. I would not recommend universal replacements that you use clamps to install.....just my $.02

landseadelb New Member

landseadelb

Posted
Posted

I just had my catalytic converters replaced on my 2001 GMC Yukon XL. For the set I believe it was around $500! The truck was running rough and missing when it was cold, which turned out to be the intake manifold gasket. Let it be known that allowing your vehicle to miss for a while can cost you big. I would be interested to know what you finally found the converters for...

jrb21284 Enthusiast

jrb21284

Posted
  • Author
Posted
I just had my catalytic converters replaced on my 2001 GMC Yukon XL. For the set I believe it was around $500! The truck was running rough and missing when it was cold, which turned out to be the intake manifold gasket. Let it be known that allowing your vehicle to miss for a while can cost you big. I would be interested to know what you finally found the converters for...

 

I Found the whole setup on ebay for about 270, Autozone for 296, and just found a Magnaflow direct fit, on Summit racing for 325, but 270 is the cheapest i have found, my local shop told be it was gunna be almost 500 for the converters and 100 bucks for labor, so buying it myself seems much cheaper, now i just need to measure and make sure that this bad boy will fit :D Thanks for all the help guys

95Sierra2500 Senior Enthusiast

95Sierra2500

Posted
Posted
I just had my catalytic converters replaced on my 2001 GMC Yukon XL. For the set I believe it was around $500! The truck was running rough and missing when it was cold, which turned out to be the intake manifold gasket. Let it be known that allowing your vehicle to miss for a while can cost you big. I would be interested to know what you finally found the converters for...

 

I Found the whole setup on ebay for about 270, Autozone for 296, and just found a Magnaflow direct fit, on Summit racing for 325, but 270 is the cheapest i have found, my local shop told be it was gunna be almost 500 for the converters and 100 bucks for labor, so buying it myself seems much cheaper, now i just need to measure and make sure that this bad boy will fit :D Thanks for all the help guys

 

 

You have to remember, alot of these smaller shops (muffler man, etc) usually either run to the dealer for their parts, or have a mark-up in place on them. It's pretty common for them to do that. If you can get the parts and do it yourself, you're much better off.

  • 1 month later...
99_sierra New Member

99_sierra

Posted
Posted

I have a 99 Sierra 5.3 and i'm having some of the same issues. The truck bogs when it's cold, it almost sounds like it's going to stall. Once it's been running for a while it seems to clear up I'm not sure if i'd rather the problem be the cats or the intake manifold. Any easy way of telling which it is?

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