cvcook

I have a 5" Flo pro exhaust with the straight thru muffler and no cat. since I took the BD twins off and put the stock turbo back on I have alot of in cab drone. I'm almost willing to trade it for a stock exhaust, but before I do, what can be done to quiet this thing down?

Ram1driver

I feel your pain. Went through the same problem a couple of months ago.
Helpful people here. I have 5 inch exhaust after the stock downpipe. I got several tips here about the Donaldson muffler. The first Donaldson I ordered did not quiet it enough for me and was discouraged. Another member put me onto the right Donaldson muffler and I made a second order. In the first muffler, I could look straight through and see daylight. The second one had a cone inside that blocked straight through flow and it made a real difference in reducing the sound. If close enough I would give you the first one (its brand new in the box with only a few miles use). It worked somewhat. I don't know what to do with it anyhow, lol. The bad news is I'm not able to get the right part number for that second Donaldson muffler I got till maybe tomorrow. It's pretty decent. I just came back from camping and tow a 9000# 5th wheel and the noise in the cab is quite acceptable. At leeast I don't have to spend the money on going back to stop. The second muffler meets highway noise standards. I ordered it from Ryder fleet parts. I'll dig the number up for you tomorrow hopefully.

TJeeper

How bout the Donaldson M100580. Thats what I bought because I wanted the quietest 5" I could find.

mossyoak11

or the donaldson M090535

Ram1driver

Made it back!

The Donaldson 100580 is the correct part number (51"length).
Can't be beat for 100 bucks. Order it from Ryder fleet parts. I got mine in less than a week after ordering. I think you will notice a huge improvement. You will not have to buy a resonator either.

Fits with no trouble under my truck.
I ordered 2 lapfit band connectors with the muffler order. They are made to fit
where muffler pipe inlet slides into exhaust from engine. They work great with no welding.

The 90... series is offroad and a LOT noisier, don't get that one.
I have that one sitting in my garage with no future. However I will give it
away to anyone who wants it and lives close enough. Send me a PM.

carl48

if you want the quietest muffler setup get a donaldson m090072 resonator and a m101181 muffler quieter than stock no drone

WhiteMule

Carl, what would be the quiet(less restrictive than stock) recipe for 4"?

tcr

This all seems to defeat the purpose of a 5" no restriction system IMO. I wonder what the pressure drop is with the muffler w/ the cone in it vs a strait through design.

mpracehemi

I use a muffler from fullspectrumperformance off ebay. I have no drone even before the twin turbos.

There are defussure cones that summit or jegs has that can be installed inside the exh. tube or muffler. Racers use them to quiet down the decibels.

cvcook

Thanks RAM1 I believe that's the one I will order. being a 10" muffler you didn't have clearance issues with the frame?

Ram1driver

CV Cook---I had no issues installing this muffler. There is enough room for this muffler. I thought I was going to have to go back to stock before buying this muffler. I did weld one more muffler hanger but may not be necessary for you. Not necessary, it is quiet enough for me. Saved me a lot of bucks. Midas muffler wanted 1700 bucks to go back to stock (they're nuts!)Get the stainless lap clamps work great! I bought them from Ryder Fleet also.
Let me know how you like it. I just wish I could give away the other brand new 90535 model that is in my garage. I will put it out for trash before long.
Hope someone wants it.

carl48

cvcook the m100585 and the m101181 is exactly the same size. i think this will help. the m090535 is the loudest the m100585 is middle and m101181 is the quitest. the back pressure for each is m090535=2,340 cfm @ 1"Hg m100580=1565 @1"Hg m101181=1630 @ 1"Hg. the m090072 resonator drops the sound by 3 to 6 db but we have never tried to install the resonator on any truck except a quad cab. there is room for both the resonator and 51" on the quad but does look like it would be to long for the short frame. it list the restriction of the resonator at 0.

carl48

whitemule the m100695 for the 4"