4in. or 5in.

Big_Mack · Feb 3, 2015

Guys deleting 2015s are you running 4 in. or 5 in. exhaust? I'm assuming the tone is different between the two.

BK39 · Feb 3, 2015

You want it loud? I put 5" on mine, too loud. Put a 30" resinator on it..........now it's too quiet lol. I'd buy a 4" if I did it all over again.

Big_Mack · Feb 3, 2015

I do want it loud but not too loud...haha

BK39 · Feb 3, 2015

It was mostly the low rpm fueling that had a drone to it, drove me nuts. All my previous trucks, 7.3, a couple 6.0s, a 6.4......had 5" exhaust, and they never bothered me, but this truck......couldn't do it.

20156point7 · Feb 3, 2015

go 5 inch its not that loud to me but some people may disagree

TheBigNasty · Feb 3, 2015

I have 4" delete pipe that runs to the 5" filter back from before deleting. In cab drone is almost non-existent. The trucks I've been in with all 5" have had bad in cab drone. All 2011-2014 trucks, but I'm sure it's comparative.

Dirty_Stroke · Feb 3, 2015

I'm glad this thread got started. I'm ready to by exhaust and torn between the two also. I read somewhere that 4" limited the truck at around 600hp. Does anyone have proof of that?? I've always ran 4" on my other diesels. I personally think the 4" sounds cleaner. But I don't want to go with it and later when I swap turbo's find out it's not enough.

UNBROKEN · Feb 3, 2015

There are multiple trucks over 1000 HP with 4"
I want quiet so I'm going with 4" plus a 24" Magnaflow muffler into the 5" DPF back kit that's already installed. If it's too loud I'll throw in an FTE resonator.

bigrpowr · Feb 3, 2015

5" for look and sound. No difference in power. I'll give a discount to anyone needing exhaust. Shoot me a pm.

Dirty_Stroke · Feb 3, 2015

Also while we are on this subject, is there any difference in sound with aluminum vs stainless?? I've heard gas burners with stainless that sound awesome.

maxxedout · Feb 3, 2015

I'm running a 4" downpipe back system, and it sounds pretty good... No drone whatsoever. If I could do it again, I'd go with a 5" instead though, just for the sound.

Dirty_Stroke · Feb 4, 2015

maxxedout said:
I'm running a 4" downpipe back system, and it sounds pretty good... No drone whatsoever. If I could do it again, I'd go with a 5" instead though, just for the sound.

Do you have a video clip of your exhaust? I could only find a couple on YouTube and they was all of the truck idling.

W219cls55 · Feb 4, 2015

I've owned 2-6.0's and 2-6.4's that have all had 4" exhaust. This is my first 6.7 2015 and decided to go with a 5" flo-pro with a 30" magna-flow muffler and I think Ivregret not having gone 4". I might take off and put 4". It "feels" like it loses power too but I won't know until i put 4". If I Decide to.

Big_Mack · Feb 5, 2015

Thanks for the input guys I'm thinking I'll just go with the 5 inch. Go big or go home, right?

TheBigNasty · Feb 5, 2015

Meh. I got nothin to prove, and I enjoy not hearing only engine noise in the cab.

MikeH · Feb 6, 2015

4" here. Sounds amazing. I absolutely love it. Was in same boat before in having to make the choice. Posted up a video at idle here:

https://www.youtube.com/watch?v=dTcmXCVpbsA

KingStroker · Feb 8, 2015

I am running 4" delete pipes with a 5" filter back behind. It was a little too loud for me, being in town mostly. So I went with an Aero resonator on the 4" section and it definitely smoothed up the sound, I wouldn't recommend the aero if you're looking to get a whole lot quieter, but it did kill almost all the cab drone. FWIW