Just wondering what would happen if I were to remove the rear two cats? Will it run like crap? Its an 04 and the o2's are are before the rear cats. I want a little more sound out of my truck but dont have the money to get my exhaust redone. Trying to save for a house. I havnet had this exhaust for long maybe a year and a half. I asked for a flowmaster 40 series but the guy accidently put on the Flowpro which he said was the same exact thing as the flowmaster just cheaper. I probably should have had him do it over again but I didnt. So what are my options? Can I remove the rear two cats without a problem? I just want to gut them out so the shell will still be there.

 

when i put flowmaster duals on both of my 07s, the installer took the rear cats off. No problems in 2 years.

 

Ok. I asked on another website and they said my truck would run like crap. They said on these newer trucks the computer would mess it up. I couldnt see how it would effect it since its the rear 2 cats and all the o2 sensors are before it. They also said that one of their sons removed the rear two on his ranger and it ran like crap and cost him 600 in repairs. I just wanted to see what you guys thought too.

 

It won't run like crap if you remove the 2 rear cats,but I think it's a federal offense to tamper with the emissions system on a pollution controlled vehicle?That is something you may or may not need to worry about.

 

Ok thats what I thought. Ya I know its illegal. Im not sure if Im going to or not. We dont have emissions testing here in Michigan. I know alot of people that have removed cats but where on older vehicles. I guess Im trying to figure out is it worth doing. Will it sound better then I have or will it sound like crap.

 

I'd do it if you're not happy with the sound.We don't have emissions testing here either. It should sound better with only 2 cats.If not than that fake flowmaster must be a POS and is the reason it sounds crappy now?? Luckily my 06 only came with 2 cats.

 

It was really quiet when I got it. I complained but the guy said its the same design as the flowmaster so its going to sound the same. Its gotten a little louder now that its broken in but not where I want it. I was thinking of taking them 2 out but people keep telling me it will run like crap and you cant do it. My one buddy said I couldnt. He kept saying cause the o2 will throw codes. But if its the rear cats there are no o2 behind it so it cant throw codes then. I was thinking of a new muffler but trying to save money for a house so I dont think thats a good idea.

 

You should be able to take the 2nd cats out, NP. Like you said, the 02 sensors are before the 2nd cats. so as long as the first cats are there.. should be good.. I can say from experience that losing a secondary o2 really does nothing to affect the way the engine runs, According to the factory service manuals, they are for the emmision system, not engine management.

 

Just an FYI.....it doesn't matter if you have emmisions testing.....if you get pulled over for too loud of an exhaust, speeding, or just a pita cop......the fines can start at 25,000 dollars for epa violations.....is that worth it to you????

 

Maybe you could do the high flow cats up front,and drop the rears.It' would have cats on it and be legal that way,plus free up some noise for you.

 

You still have cats on it, the police wouldn't know that you removed 2 of them., if you still had 2 left. I live in BFE in illinois, no emissions testing here, and the local cops have big loud trucks too!

BTW, is overfueling a diesel a EPA violation? I see lots of that.

 

Well there are alot of trucks around me that are way louder than my truck will ever be. People are running straight pipes with no cats and all that garbage and makes their truck sound like crap cause its so loud. My plan was just to cut a big area out of the cat and bend the tab over and gut it out. Then when I was done I would bend the tab back weld it then grind the welds down so it dont look like its been messed with. I dont think I would have a problem. Just wanted to make sure that my truck would run fine cause people say it wouldnt but never gave a real explanation.

 

Really worth it??? No performance gain....marginal noise change.......highly illegal.....even replacing stock cats that are working on lower mileage or newer vehicles is illegal

 

With the right ecm programming, you can make it run but, even though you don't have emmissions testing in Michegan, the way the fed regs are now, any AQMD inspector/agent, law enforcement (this includes USFS Fish & Game, Etc.) can impound the truck, tagged as a gross pollutor and in addition to the tow, storage fees & fines, you get to go sit in a courtroom where a judge will determine if your vehicle is to be returned to you or salvaged to a recycler- and you are not even allowed to be involved in the discussions.

to me IMHO, it's just not worth it.

 

Ok, do any of you guys have certain knowledge of vehicles being taken off the road by any half-*** law enforcement personel or are you just making your point by throwing out hypotheticals? There are many things that could happen but never do. It is not like he will have black smoke emmiting out the back.