Exhaust Question

[Snoxracer]

Just got my replacement muffler from DPP, it is a MBRP. Anyway I am going to install it today but was wondering if I should take the CAT(resonator) out or leave it in. I was wondering how much restriction the cat has (is it straight thru or what?) and if I do take it out will it give me a drone?



Thanks, Dustin

 

[p-Bar]

Probably the cat is restrictive. The dealer may give you some crap about it and also you are breaking Federal law by removing it.

 

[Jeff_K]

I would leave it on. The cat on your truck is not very restrictive at all. It also seems to sound better when the cat is left in place from the 04. 5+ trucks with aftermarket echausts I have heard.

 

[DPKetchum]

Have read that the cat is NOT very restrictive and really no point in removal. Some have put the cat BACK on after whatever muffler was TOO LOUD. Read that the cat may affect egt about 75 degrees is all. Leave it on and have no worrys.

 

[RaymondSmith]

Dustin,



Please be sure to post your decision and the results. I really like the factory sound but wouldn't mind a free flowing system.



Thanks,



Ray

 

[TCDiesel]

Very little benefit in removing it unless you plan on future hp over 450,The stock muffler is were all the restriction is occurring. especially when you start to mod.

 

[Cattletrkr]

Leave the cat alone. Left mine on in case DOT decides to look under truck some day. Not that they'd know the difference between '04 and '04. 5, but... Truck sounds great with 4" glasspack. Louder than stock, but not bad. Towing it's borderline annoying, but I had to have some noise. Mich XDE-MS are louder with windows down than the exhaust is. MBRP should give you similar results as it it a nearly identical muffler.

 

[Snoxracer]

Its on?

Well I cut just the factory muffler out with a sawzall and installed the MBRP muffler and S pipe, and left the CAT in. When I had the muffler off I shined a flashlight in toward the Cat, and as far as I can see it looks like a screen. Anyway, I took it out for a test drive, without trailer, it sounds pretty good but a little loud when the go pedal it pressed hard. Just crusing it is quite, but bellers pretty good under load. It didn't seem to have much of a drone but will have to tell when the trailer is on. I had a Banks monster exhaust on my 2nd gen and I think I liked the sound of that system better.



Snoxracer

 

[RaymondSmith]

Snoxracer,



How do you like the sound after living with it for a month now? If you had it to do over again, would you? I am really on the fence about getting a MBRP muffler for my 05. It actually doesn't sound too bad stock. I'll tell you why I'm worried though. Just the other day I was in a store parking lot. I could hear a 3rd Gen coming up the hill into the parking lot with a modified exhaust. It sounded like a stock Cummins that was mated with a souped up Honda. It had the weirdest exhaust note I had ever heard. I certainly don't want to end up with something that sounds like that. I'm looking for something deep and authoritative. I'm hoping to get that with the MBRP replacement muffler.



Thanks,



Ray

 

[MMeier]

Lots of 3rd gen owners(myself included) are happy with the Magnaflow muffler. Do a search and see what you think,

 

[Snoxracer]

Well after running it for awhile I can honestly say that I like it! It doesn't seem loud with the trailer, I think that when I first put it on I was used to it being so quiet, but now being used to it I like. I had my girlfriend drive it the other day so I could listen to it going down the road and it sounded really good. So I would say that for 150 bucks I am happy that I went with this muffler!

Thanks,

Snoxracer