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2003 1500hd exhaust resonator or cat?

Discussion in 'Chevy Trucks' started by plowin207, Jan 20, 2013.

  1. plowin207

    plowin207 Member
    Messages: 89

    ok so i feel really dumb having to ask this but im not sure what is what and don't want to do something that will cost me more money since money is kind of tight right. my truck has an exhaust leak right under the passenger door. it is after the flange there is a peice that is about 6 inches long i'd say and fat like a 2 litre bottle that broke around the weld and slid back about a half inch. i tought it was a resonator and was just going to replace it with a peice of pipe. but then i noticed a sensor after it, now im confused wether its the resonator or cat. so my question is. is this a resonator or the cat if its the resonator can it be removed with out a CEL comming on or will i get a light and my other question is if it is the resonator can i remove just one or do i have to remove it off both pipes to keep it equal were it is dual all the way back to the muffler?

    sorry for the long post and any grammer or spelling mistakes.

    thanks for the help
  2. Spool it up

    Spool it up Senior Member
    Messages: 912

    , straight pipe it , if you have a mechanic as a friend :mechanic: kill the cat , it just boggs it down. its just a treehugger idea . engines were made to breathe freely and will stay cooler by the mile .
    Last edited: Jan 20, 2013
  3. South Seneca

    South Seneca Senior Member
    Messages: 473

    I believe what you're describing is the cat. If that's the case, does it have to pass a vehicle inspection in your state?

    In most cases it wouldn't pass if removed.
  4. Spool it up

    Spool it up Senior Member
    Messages: 912

    not in pa . but if you know someone :mechanic: hard to pass carbon emissions parts per million
    yes kill the cat , its just a restrictor .
  5. plowin207

    plowin207 Member
    Messages: 89

    ya i thought it was the cat when i saw the sensor after it. the exhaust comes out of the header runs through the pipe there is a spot on both sides that is like 4 inch think and maybe a foot long goes back to 3 inch pipe then there is a flange and after the flange is the peice im talking about then it is piped to the muffler. im confused about it being a cat or resonator becasue in my old truck the cat back kit i got was from the flange back so i figured it would be the same and the cat was the one before the flange. like i said im not positive though. and we do have inspections but no emmisions test but part of the inspection is there has to be a cat in the exhaust system. trust me i would love to delete the cat and resonator and make the exhaust free flowing.but i don't know a mecanic that can always get me a sticker.

    REAPER 2000 Club Member
    from 60050
    Messages: 2,228

    Is this what you are looking at?

    chevy cat.jpg

    If so you may be able to have a exhaust guy weld/fix it up to save some coin. If it is plugged at all then you must replace if you have state air inspections like we do here.
    It is your choice to do or not to do if you do not. Personally I would replace to stock to keep things in the norm as far as sensors and engine. Thumbs Up

    chevy cat.jpg