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Discussion Starter #1
Hello,
New here. I have a 2003 2500HD 6L Silverado. Awesome truck. One of my catalytic converters was stolen a couple nights ago. Sliced it right out.
My questions are concerning repair. My short term plan was to just get a couple feet of flex pipe to close it up. Long term i want to replace the converter. If i run with only 1 unit for awhile will this be harmful in any way and will i get a bunch of alarms? Thanks
 

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Toxic Masculinity
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You'll get a DTC code on that one bank from the outboard o2 sensor (o2 behind the converter). That in itself (the code) will not change the fuel delivery like the inboard (02 front of the missing converter). That one bank (side) will probably flow more efficiently and the inboard o2 should still trim the air/fuel to 14.7:1 stoichiometry. If there is to large a swing for the o2 to trim you might see a limp mode issue where the PCM kills power.

Wouldn't drive it long like that though. You could buy a couple high flow cats and have your muffler guy install or just buy a new factory Y pipe but I'd replace the pair. Another option If you don't have state inspection you could delete both and have the DTC codes disabled in the tune.
 

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Discussion Starter #3
A lot of this is Greek to me but I get most of it. I could delete them...I live in Montana. If I did delete them what would follow? Explain the DTC code thing and tune plz. Thanks for the response.
 

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Toxic Masculinity
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Without the converter the outboard o2 sensor knows there is a catalyst Issue and kicks a "Diagnostic Trouble Code" (DTC). It just tells the driver you have a cat Issue... that's all it does lighting the "service engine soon" lamp on the dash.

Years ago I removed my cats and of course I had the light on the dash. To turn off the light I bought a electronic "o2 simulator" and wired it in where the outboard o2 sensors were. Today I have tuning software and simply can turn off the light in the tune, so I no longer need to use this simulator. I think I payed like $40 for box below.

 

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Discussion Starter #5
Nice thank you. Where does that little guy wire into?
Did you notice any performance improvements after removing the cats? My biggest concern is fuel mileage. The HD 6.0 is a bit thirsty with the lower gear ratios
 

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Toxic Masculinity
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They wire into the o2 harness. Not sure you can still buy these as the Feds have cracked down on electronic simulators. A google search may give info. The engine is more efficient without the old factory cats. You can get a couple high flow Flowmaster cats for around $60 a piece and have your muffler guy install. If you go with the OEM factory cats be prepared for sticker shock plus the install labor.
 

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Discussion Starter #7
Ya i can about imagine what OEM pieces cost.
If i remove the other do i need to do a tune of any kind of will the DTCs just be annoying?
 

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Discussion Starter #9
Ok thanks. For the time being i may just remove both and splice in some flexible pipe and deal with the DTCs. I will replace them but i dont think its in the cards right now. Thanks a bunch for your help RedXray
 

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I admit that i try to be a little green where i can. I have no issue with replacung my converters. My wife has severe asthma too, so the exhaust odor could actually be quite hazardous to her.
BTW, i know no redneck who can use words like "stoichiometry" and "quintessential" in a proper sentence. And i am from Montana. ...i know rednecks lol!
 

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Toxic Masculinity
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I admit that i try to be a little green where i can. I have no issue with replacung my converters. My wife has severe asthma too, so the exhaust odor could actually be quite hazardous to her.
BTW, i know no redneck who can use words like "stoichiometry" and "quintessential" in a proper sentence. And i am from Montana. ...i know rednecks lol!
That changes everything when someones health & comfort becomes an issue.

Now you've met a redneck from South Carolina, I think the word "redneck" was coined just right here! 😂

From a true "Sons of Confederate Veterans" my great great grandfather who was wounded & captured then imprisoned in Sandusky Ohio until the wars end. He was the patriarch of our family coming from Ireland then settling in Spartanburg, SC.

God Bless Dixie

 

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every one of my neighbors had there converter stolen when i lived in the city i just ran an extension cord to my car for a "engine heater" and left the bare wire sitting on the frame. at two am in the morning i heard a scream and swearing and went out and caught the tweaker breaking into my car and later the little shit actually called the cops on me. they came out told me to fix that wire with a smile on there face and drove off. the neighbors followed suit and crime dropped in the neighborhood 90 percent. i moved not to long after that it was getting to crowded and noisy.
 
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