6.7 Exhaust Sound

[DPrew]

I loved the way my 2002's exhaust sounded with a free flowing muffler. I actually had the muffler installed backwards to act as a resonator. It sounded great but had no annoying straight pipe drone.



With the DPF and a free flowing muffler do the trucks sound as bad *** as the older trucks or does the DPF quite things or change the tone. Any tips on the best deals for DPF back systems? My last system was from Warp Speed Performance and it held up great.

 

[Hoefler]

You can remove the muffler with very little change in the exhaust note.

 

[DPrew]

Is there any drone at all or does the DPF kill the drone since it's far from being a straight pipe from the turbo.

 

[Hoefler]

Really no difference, not worth the time nor effort in my opinion.

 

[2Rowdy]

Save your time and money. Makes no difference at all. Unless you do the full delete package.

 

[Austin Diesel]

i did pull the muffler and saved it to the shop it is a straight thru design wiith 1/4 inch holes not to effective design internally just there for the EPA?





Installed Magnaflow dpf back stainless dual 4" 5" twin tips and muffler deleted it is a little louder but not much the smog stuff kills most of the noise from the 6. 7 . and it passed inspection too. and warranty is intact , the cheap kit supplied u-bolt muffler clamps would not hold the heavy dual tips up on a bumpy road they would sag so added a hanger to support tips and migged the joints with a tack weld and used stainless band clamps



the polished 5" stainless tips are a little discolored from the heat regens would like to fabricate or buy /build or install the banks cool cuff to see if it reduces exhaust temp tip discoloration



it does have a nice tone no drone little louder over time but not much



austin diesel

 

[DPrew]

I think I had read that you need to do stainless tips with DPF trucks because the chrome can't take the heat.

 

[Hoefler]

I think I had read that you need to do stainless tips with DPF trucks because the chrome can't take the heat.

It is the other way around

 

[CUMMINZ]

I added a 5" DPF to rear pipe many months ago. My wife tells me that I need to add the chrome tip. Her logic is pretty sound. The 5" gave me no horses but the chrome tip will add about 20hp.

 

[run2trouble]

ago. The 5" gave me no horses but the chrome tip will add about 20hp.

:-laf:-laf



6" will give ya 35hp.

 

[mpaulson]

I'm straight pipe, all the junk removed, and it is a bit louder, but not much difference inthe cab. I wish it made more noise, I miss my 12v and 24v bark. With it all off, the egt droppedabout 150 degrees. I've got stainless tip and no decoloring issues, of course mine dosen't get hot due to it never feels the soot build up for a regen.

The only time it is noticable louder is when towing, it can be a bit anoying at times, but the steady hum will put the kids to sleep on long trips.

 

[Austin Diesel]

It is the other way around

that is correct i think the genos catalog says it too ,the discoloration is not to bad or noticable, they are welded on also



stainless doesnt handle the high heat well



austin diesel

 

[Vaughn MacKenzie]

The exhaust note is definitely different than 2nd and 5. 9 3rd Gens, due to the off-center outlet and not having a divider between front and back cylinders (among other things). Exhaust note has more of a "rumble" or throb to it:

YouTube - 6. 7 Cummins 7-in stacks (Part 1)
YouTube - 6. 7 cummins MegaCab Dually Donut
YouTube - 6. 7L Strait pipe

 

[WDixon27]

this one kinda reminds me of a old two stroke YouTube - who says a 6. 7 can't smoke

 

[Scrappy]

this one kinda reminds me of a old two stroke YouTube - who says a 6. 7 can't smoke

I kinda like it!