dgibbs

Picked up a Donaldson 51" muffler today, part #M090544, to replace the stock one on my 2003. Stopped by the local CarX place and asked if they could install. They said they'd do it for $50. I said go for it.

Once they had it on the rack and looked good and hard for 5 minutes, they called me over to explain they couldn't install it. Guy said it would hit the frame, plus it would hang too low causing the tailpipe alignment to be way off. We talked several minutes about it but the end result was telling him thanks for looking at it and c'ya later.

Took the truck down the road to the Meineke shop. Told the guy what I wanted and he said he was too busy to get me in tonight but that he'd put it on the rack to see if it could be done. Put me on the only open rack and turns out the truck was too heavy for it. The only other rack was taken up by a Ford Ranger getting a brake job. Said to come back tomorrow night.

For those of you who have done this mod, especially on an 03, what advice would you give me to tell the muffler shop? I'm thinking I need a 4" to 3.5" reducer to fit the stock pipe to the Donaldson inlet? Do you also have to rotate the stock pipe before the muffler 180 degrees to line up with the Donaldson inlet? Any words of wisdom will be greatly appreciated.

Big Bob

dgibbs,

I had Meineke install my 51" Nelson and had no problems at all. The did a great job!

You do need a 3.5"ID to 4"OD adaptor to attach the muffler to the pipe to the turbo.

Yes you do have to rotate the pipe 180* to line up better with the muffler.

45auto

Which one is better, the 34" or the 51", how much difference in sound.

AK RAM

The shorter mufflers (26" & 34") sound absolutely wicked with a set of stacks. I really like that setup. If your pumping it out the side like most of us, I would recommend the 51" just to be safe. My 34" sounded perfect when I first put it on, but as I have bombed the truck more, I have noticed it has gotten louder. Opening up the exhaust flow with a turbo that had a slightly bigger exhaust side made the most dramatic change. It is still not too loud for me, but if it were any louder, we would have issues. It mainly gets my attention when I have a car riding beside me. A few folks here did not like the shorter mufflers, but I really haven't heard anyone complain about the longer one. If you want good sound, authoritative without obnoxious, the 34" will fit the bill, but it will change if you go swapping manifolds and turbos and stuff. Soon I'll swap the turbo again and go even bigger. I suspect I'll have to do something to quiet it down at that point.

SoCal-305

AK RAM and others,

Do the Donaldson or Nelson mufflers on the Dodge have a harsh whistling/fluttering sound to them. I've heard several Ford "Hav'n a Stroke"s with a performance muffler on them, and the fluttering sound is so bad, it sounds as if the engine is missing or the turbo is sick.

Thanks!

Forrest Nearing

the third gen Cummins has a little bit of flutter to it, but NOTHING like a Powerhoax!!! the old 7.3's did it pretty bad... the new 6.0's sound like there's something wrong w/ them! LOL!

your truck will sound close to stock w/ that big 51" muffler on it. I've heard straight piped third gens, and they barely have a hint of flutter.

Forrest

Toby

Does the Donaldson muffler fit right into the stock exhaust system? I think I am going to get one soon and just wanted to know if I would have to get adapters for it.
Toby

dgibbs

Toby - Is your new truck a 2002 or 2003? I don't know about the '02, but I've learned a few things about the '03 since starting my quest for better air flow. To answer your question, yes you'll need a 3.5" I.D to 4" O.D. adapter for the inlet side of any new muffler with a 4" inlet. From my understanding, the '04 and '04.5 are different stories.

dgibbs

Thanks for the info Big Bob. I stopped by the Meineke shop today and they said they'd do it. They think it will take about 1 - 1 1/2 hours. They're going to charge me one hours labor to put it on. Is that about the same amount of time they spent on yours?

Big Bob

I think I paid the $66.00. However, the first one I put on came from Fleetpride and they sent the wrong muffler. So I then went to Cummins Northwest and got the right Nelson. Meineke then installed that muffler at no cost! It wasn't even their problem, but they treated me more that fairly! I will definately return when I need more muffler work done.

Toby

dgibbs thanks for the info, My new truck is a 2002, I had a straight pipe on my 2500. I liked the way it sounded but if I could find something somewhere between stock and straight I would be really happy.

AK RAM

I have heard a few of those, so I believe I know what your talking about. Sounds nothing like that.

dgibbs

Install is done! I actually had it installed at Midas, not Meineke. Took an hour and 20 minutes. The guy welded the adapter on both ends, the tailpipe to the muffler, and reused three of the factory hangers to weld the muffler up. He then painted all of the welds with black paint to prevent any corrosion. I don't know a thing about welding but I think he did a great job!

It spools faster but I can't really determine yet if I'm seeing a drop in EGT's as I was too busy stomping on it all the way home rather than doing my normal pace to and from work. It sounds much better than stock IMO, and has no droan. Probably not loud enough for some of you but definitely producing a nice sound to me. Noticable difference in turbo sing as well. Next is a tip. Time to utilize the search engine. Any recommendations?

BTW - My only concern is if it's producing enough back pressure. Thoughts?

Forrest Nearing

the turbo is producing all the backpressure you need

SoCal-305

dgibbs,

How much did it cost at Midas for the installation? I'm going to look for this muffler now and might use your information to get installed. (or maybe I should use that $$$ to buy that welder I've been thinking about)

Thanks.