Mine has a flo pro resonator installed in the delete pipe. Just towed an enclosed trailer this week. Was quiet even in the hills. You can add a muffler in there if you want. The resonator was $100cad and a muffler would be around the same. Delete pipe is extra but you’d be buying that anyway.

 

Gotcha, thanks.

The one I'm looking at already has a 5" straight pipe - can you just cut it and stick the resonator and muffler in line? Assuming they both get welded in? Or clamped?

 

Yup. You can buy5” resonator and mufflers too. Semi Truck shops have them if nowhere else.

 

Does that kill the mpg/power of the truck, or is it not much difference in the end?

 

No difference in power

 

Yeah you can put a muffler on it. It won’t change anything but the sound in any meaningful way. Personally I wish my truck was louder but I’m not in a rush to delete anything. My emission system isn’t throwing any problems and it barely sips DEF. I love the sound of 12 valve tunes on these engines. It’s more about the rattle of an old diesel than the exhaust note for me though and I’m rambling now so I say slap a muffler on it and call it good.

 

I've got a 5" Flo Pro Turbo Back Exhaust with the Flo Pro Muffler. It isn't bad.

There are different opinions on the 4'' vs the 5''

I know, the guys that did it cussed it pretty good. But I wanted 5'' based on the opinions of some in here. Call it whimsy if you will. Might have been a waste of money. Don't know

At slow speeds, you can hear it more at low RPM when it's getting up to speed. Haven't towed anything yet. It's really fresh so I'm not gonna tow anything for a little bit. Still don't like the transmissiion shifts and the lock up points. But that's me, I think. Maybe. Plus the Exhaust Brake changed quite a bit. And it stays on when you shut it off and re-start it, where it didn't before. Oh well.

But once it's at cruising speed (in mine anyway) you can't tell the difference. much

 

Everyone's definition of quite is different. I see guys saying it's not much louder then stock straight piped, others saying it is just like stock with a muffler or resonator. For me a resonator AND a muffler should get it back close to stock quiet. I have a 30" MBRP muffler now but putting a resonator on it as well this week. Loud was fun when I was 16, now I just want to enjoy the silence or hear my radio without blasting it.


.

 

I was thinking about doing that as well. Is it difficult? Are there parts/pipes to buy? Is it a PITA.

I like my comforts and I like hearing the radio

 

If you are deleting and want it quiet, stuff in the largest straight thru muffler that will fit, like a Donaldson.
I'm personally think that a common rail Cummins sounds terrible straight piped or minimal muffling.
Some of the loud CR Cummins are fine when empty around town but when loaded up a long hill will drive you nuts with drone.

If you haven't been around a diesel truck (or gas engine) that doesn't have a catalytic converter lately, just be aware that it will smell exactly like any old diesel truck that you have followed lately.
My wife nearly killed me when I removed my cat many years and I had to re-install it shortly after I removed it.

Keeping the cat converter in place while deleting is an option that I recommend. It will quiet things down even more and keep the harsh diesel smell reasonable, with no effects on engine power.
Plus keep wifey happy!

 

If you are deleting and want it quiet, stuff in the largest straight thru muffler that will fit, like a Donaldson.
I'm personally think that a common rail Cummins sounds terrible straight piped or minimal muffling.
Some of the loud CR Cummins are fine when empty around town but when loaded up a long hill will drive you nuts with drone.

If you haven't been around a diesel truck (or gas engine) that doesn't have a catalytic converter lately, just be aware that it will smell exactly like any old diesel truck that you have followed lately.
My wife nearly killed me when I removed my cat many years and I had to re-install it shortly after I removed it.

Keeping the cat converter in place while deleting is an option that I recommend. It will quiet things down even more and keep the harsh diesel smell reasonable, with no effects on engine power.
Plus keep wifey happy!

Did they have any cats in 13’ up?

 

no cats '13 and up

 

They definitely have a catalytic converter of some kind. Separate or integrated depending on the year of the truck and Def or no Def.

The truck I was helping to delete (2012?) had a pre-cat in the downpipe that we ended up re-installing a few weeks later.
I'm not sure if all the trucks have a pre-cat in them.
Even the pre-cat quieted things down and reduced the fumes.

On one 2003 truck which had a 3.5" exhaust and no cat from the factory, we ended up installing a 4" cat from a 2007 truck after the aftermarket 4" exhaust was droning terrible with a full load up a hill.
The cat reduced the fumes totally and eliminated most of the drone.

Just my opinion and experiences.

The fumes and smell may not bother you (or your wife!).

If you are not towing, you can get away with a straight pipe exhaust, but as soon as you load it up and head up a long hill, a straight pipe will drive you nuts.

 

A very good resonator is made by F-T-E diesel. Install it at the bottom of the down-pipe, just as it straightens out.

 

Deleted is one thing and going to a fixed vane turbo is another. My 12 was deleted with the stock size 4" and the tiny muffler just ahead of the axle and it sounded really nice with deep tone. Then I put on the BD kits and it got MUCH louder and borderline on drone. I added a 51" muffler and I still had to stuff the chambers of both mufflers with fg to get it comfortably quiet. I didn't like the hissing of the 4" tailpipe so I changed it to 5". It still has the deep tone and we can talk in the cab while towing... mui bueno! , Outside, by the tailpipe is a ROAR and I can't have the rear slider all the way open for very long. Nobody drives in that blind spot. Craig

 

I made my own delete pipe section with a 30” FTE resonator. Welded a 3 bolt flange right to the resonator and bolted it to the down pipe. It’s barely louder then stock if at all.

 

4" flo pro here with muffler. It's pretty loud on decel using the exhaust brake, but I believe the manual trans have better exhaust brake capabilities than an auto. It's not too bad accelerating, I imagine a 5" would be lots of drone.

 

I run a 4 inch with a spiral core muffler. It's perfect, IMO!

 

Don't start the engine, it will be real quiet then! 😝

 

So a 5” with a resonator and muffler will be quieter then a 4”/resonator/muffler?

 

With the DPF and SCR cat gone, you have about a mile of free room under there for as big of a muffler as you would want. Get a long straight through muffler made for a 18 wheeler and it should be plenty quiet.

 

Why use a cat? A muffler will work better and it's not an emissions component.
The delete was to eliminate emissions hardware.