Besides the DPF, what other components does the exhaust system comprise of? I took the cap off the bed yesterday and was driving around with the rear window open. I can hear the woosh, but would really like to hear more of the turbo. I am -dpf, but stock besides that. What can I do to bring some sound out of the truck without droning?

 

Get a turbo back kit with a high flow muffler

 

No real point in doing the down pipe... Honestly, you won't gain much of anything besides fitment issues and a headache.

As far as sound, 6.4s really don't have any turbo whistle at all. The hybrid compounds act pretty much as a muffler. That's why at wot when the veins are open it has an amazing growl but at idle it just sounds like an angry hairdryer. You can gain a little at idle and when you let off by getting a set of tunes that command vgt open at idle. But the only true way to get more sound out of a 6.4 is going to be a big single turbo. And for a DD a single really isn't the way to go.

You can get a bit more of a 6.0 grumble with 6.4 exhaust manifolds and aftermarket up pipes (BD has the best kit). But again, the turbo setup is going to muffle any turbo whistle.

-EDIT-
Doing a full 5" straight pipe is going to get you the biggest gain. But even then the hairdryer noise is very pronounced.

 

If you want more of a turbo sound delete the DOC, the down pipe will help EGT's a little, but deleting the DOC will give you a throater sound but not much turbo, doing a AFE open style intake will let you hear the turbo more if thats what you want.

 

Either way on a 6.4 the only way to pull more turbo whistle is 6.0s manis and hd up pipes....

Or go all out and drop a single in. These trucks don't whistle.... Nor do they grumble, or have any real excess noise to them. The turbo setup does a damn good job of quieting things down.

 

The 6.0 manifolds and up pipe will not change anthing at all as far as the sound. They will how every flow better and slightly lower EGT's. The biggest reason to change to the 6.0 manifolds and up-pipe are the elimination of the weak flanges set-up the 6.4's has.


I do agree the 6.4 will never have the turbo sound of the 6.0's simpily because the sound is muffled thru the second turbo. However, you can generate a lot turbo sound on the engine side with an aftermarket intake like the AFE stage II or the no-limit intake set-up.

 

They do actually change the exhaust note... But its going to have about the same effect as changing the down pipe to a 4"...

But yes the point of doing it is in fact for air flow. Same as an egr delete and cold side pipe.

With a single or a non vgt compound setup a 6.4 has quite a whistle to it though.

 

I wouldnt do those mods unless i had a good reason to lift the cab, lol, sound is not a good reason. But these do have catalytic converters?

 

Yes, its pretty much built into the dpf. They bolt together.

 

both units have been replaced already... and I have a S&B intake with the cleanable filter. I tried removing that clear cover from the filter housing but that did not seem to have any effect on the sound

Met a guy with a 2010 that has a 5 inch exhaust and it does sound better, but no where near the sound I hear some of these tuned 6.0's leaving the gas station.

 

I had the AFE Stage 2 CAI and could really hear the turbo. I just upgraded the AFE to a No Limit CAI. AFE's for sale now.
I have 4" turbo back, no muffler, no drone, but it is extremely LOUD when pulling a load up dirt mountain roads. Lot's of turbo whistle. Will have 72mm LP turbo in about a week.

Maybe the people saying there isn't any turbo sound have mufflers?

 

Exhaust diagram

 

6.4s don't have the traditional whistle, they have a hairdryer noise. However... When the pedal is to the floor you definitely hear that turbo... But everyday driving its nothing like a conventional vgt turbo.