LooseBoltsRob

Okay, I just grabbed a killer deal on a T304 Magnaflow 5" system, but I am not using the muffler since it necks down to 4" at the muffler core. After reading a post from a member stating that the Donaldson M090535 is a 51" 5" straight through muffler that's 9" in diameter, I grabbed one from Ryder Fleet products for $67. It hasn't arrived yet, but another member who's is the same position as me, just got to play with a M090535 and he said it's NOT straight through. I don't know if it's just simply baffled like some of the other Donaldson and Nelson mufflers, or what. Maybe the M090535 was mislabeled in one of the situations. Anyway, I know there's plenty of talk about the correct number for a Nelson or Donaldson that's straight through in 4", but virtually no talk about a 5". I am going for a true 5" system that's no louder than an aftermarket 4", maybe even quieter. My M090535 will be here sometime next week, but if it really isn't straight through, and it's not just a small baffle that can get bashed out, I need to order something else.

Does anyone have any parts numbers of straight through 5" mufflers? Or can I get confirmation that the M090535 definitely is straight through and we just discover that the one that wasn't was misboxed? The specs of the M090535 are great....over 3200 CFM at 3", 12-17 db attenuation, off-road use. I cannot find any flow specs on Nelson mufflers, but they have both SS and aluminized versions of a 5" in/out that's 51" long and 9" diameter, as well as one that's around 10-15" shorter.

Using donaldson's specs, they don't seem to have a 9" diameter muffler that's 5" in and out that flows better than the M090535. They all flow less except for one other that matches the flow.

Thanks for any help!

PowerDually

I just mounted mine on my truck.

The muffler had four pieces of metal that are bent like in pie section that are in quarters that meet in the middle.

I took a 2" piece of pipe and jammed it in their and made it truly straight through. Took all of 10 minutes.

You cannot beat how quiet it is compared to the MBRP muffler that I had before when cruising.

It is worth the wait to get it. Do a search for the donaldson and there should be a recent thread that tells you the same thing i just said because that is the only way I knew to open the ID up before going to the muffler shop.

good luck

LooseBoltsRob

PowerDually,

Was that the M090535 5" that I mentioned? I'm okay with just straightening the baffle if that's all it has. Thanks for the advice!

tcr

Rob, the baffle does look easy to knock through and you might have about a 4" opening. It's just not what I was looking for. The muffler I ordered in to look at on Mon is 5"in/out for a Detroit Diesel, their 2 stroke design requires a muffler w/ hardly any backpressure. There model#s start w/ LBP(for low back pressure), I think the one I'm looking at is a LBP5510, it has a 10" housing diameter which might be a problem w/ Magnaflows hangers(too close to the frame and hanger assemblies). I'll let you know soon, I think we're both on the same mission.
Tom

CowboyDave

Muffler??? Whats this muffler you speak of???

tcr

5" straitpiped is either too loud or I'm too old @ 31.

jmccart

Check this out, I added photos.

https://www.dieseltruckresource.com/...d.php?t=130323

CowboyDave

Oh crap, so thats what I have to look forward to this year. I turn 31.

Luvnacumns

Did you get the muffler yet?? Keep me updated I am wanting to do the same with a 5" system but haven't found a quiet muffler. Also did you keep your Kat?

prattman

Here's a picture of the Donaldson M090535 muffler looking through the inlet I posted from the TDR. It is a straight through muffler.

LooseBoltsRob

Awesome...this is great...lets just hope mine is the same way when it arrives. It should be here in the next day or two.

Thanks!

LooseBoltsRob

No, cat is long gone, and will stay that way especially with the 5" system. I really hope this works out because w/ the new turbo, my current little 18" long MBRP replacement muffler from DPPI drones pretty badly at 70 mph with only a 2500 lb trailer. Unloaded it's quiet until 80 mph, then the drone kicks in.

LooseBoltsRob

Well, it arrived today. It's defintely straight through and identical to prattman's photos, so tcr...the muffler you spied must have been misboxed. You can see the only problem with the muffler in prattman's photo...it's a 4" neckdown for about 2" The perforation tubing stops and the muffler goes fully open (to the outside wall of the muffler) for about an inch or so where it then flows into this 4" bell shaped opening, which protrudes about 4-5" into the fully open section....basically it's a baffle sort of deal where some of the exhaust will go around this bell shape instead of immediately through it and help slow down the flow, thus reducing noise. The bell is created by pinching the 5" pipe several times enough to shrink it to roughly 4". With something just under 5" in diameter with a rounded top (like the oxygen tank iron cap, just larger in diameter) that can be forced through this section, it should easily straighten it out some. That's ALL that's needed to make it a true 5" straight through. As it is now, it probably flows better than the Magnaflow muffler since it's just a 1-2" long section of 4" vs. 24" of 4" on the magnaflow. If and when I find an object to open this section up, I'll have the ultimate 5" exhaust

Luvnacumns

Rob, where did you get this muffler at? I just ordered a 5" system and I'm goona try it without the kat and then if it's too loud I am goona get a muffler...

Shane

LooseBoltsRob

Ryderfleetproducts.com has them for $68 and shipping for orders under $100 is only $7.95....a STEAL for how big this thing is to ship.