You guys are killing (well at least my bank account).

[DaveMorris]

Well the truck that I wasn’t going to touch because STOCK it has more than enough power to pull my jeep and trailers has the hood opened in the driveway just as much as my jeeps. Now after having the edge EZ box, and ordering a AFE Proguard 7 today; I am looking at what to do to make the exhaust a little free’r flowing but not any louder than possible.



So here are my questions, is there a muffler replacement that will open up some CFM’s that doesn’t produce any more (or little more) sound than stock when normal driving?



Should I just skip the muffler idea and go with a whole new system later on?

If I do go with the exhaust route is there a down fall to the 5” system?





I want more flow, I don’t need the “most flow”, and I want to keep it fairly quite since this is our primary weekend family vehicle.



Thanks in advance,

Dave

 

[tURBOdIEZEl]

straight pipe it! = D LOL

 

[GWDiesel]

EX. Noise

Beware the dreaded power drone,1650 to

around 2300 RPM under load. If you modify your EX. Do what you want but keep this in mind, I found out the hard way

I removed a 5" EX. back to stock because the 5" would not clear my new Hellwig sway bar. It is great to listen to the sat. radio now

and the 5" muffler was baffled. Now i can

hear the commands from the GPS more clearly GWD

 

[timjones]

The Donaldson M90544 flows just about 3x's as much as the stock muffler and is just as quiet give or take a little bit. Beware though it is Long: 4" in/out 51" long and 9 dia.

 

[GWDiesel]

part number

Thanks for the Donaldson part#,I will be going to a 4" S/S EX.

later this year. I don't mind the weight it is opposite the Fuel tank.

If the Diesel price's don't drop soon I will park the 03 and drive

just my 1986 Golf diesel. GWD

 

[hotram03]

Jannetty Racing has very nice 4' systems, 5 is a little much unless you plan on mega power, course once you get started its hard to stop LOL

 

[Prairie Dog]

Tim, did the Donaldson help or add to the drone and did you notice any difference in your ex temps?



Scotty

 

[FastEnough]

Donaldson

I bought the Donaldson Muffler Part #M085171 at my local Freightliner Dealer. 4"in and out straight through 40" long about 9" round $50. 00 sounds good. You do need to have a muffler shop do a little modification due to it being a straight through.



I added the part# to my sig because I keep having to look it up myself.

__________________

 

[FastEnough]

Originally posted by Prairie Dog

Tim, did the Donaldson help or add to the drone and did you notice any difference in your ex temps?



Scotty

The muffler has no drone at all. And it did help me with egt's. The muffler is straight through 4".

 

[timjones]

FastEnough,



Took the words right out of my keyboard



But I never did have a drone to speak of. A bit o' noise 2000 to 2200 but the radio just went from 12 to 14



Scott,

It droped the egt's, abit I could hit 1150 stock now same hill about 1100 and the waste gate doesn't hit 26 drop to 23 then slow climb to 24. 5, it jumps to 22 then slow climbs to 24. 5.

 

[Prairie Dog]

Thanks for the info guys. Does anybody make a 4" down pipe that allows you to keep the stock elbow? It would sure be nice to make it a true 4' all the way through while I've got it apart.

 

[JThiessen]

PD:

Banks is the only one so far that replaces the downpipe. I like mine, close to stock dB under 2K, over 2K it just gets deeper and louder - with no drone. BUT - still not sure if it was worth the 625 compared to a Rip's system for @400. I remember someone saying that they were going to find out if banks would sell them just the down pipe, but I never saw a response.....

 

[Jeremiah]

Originally posted by DaveMorris

Well the truck that I wasn’t going to touch because STOCK it has more than enough power to pull my jeep and trailers has the hood opened in the driveway just as much as my jeeps. Now after having the edge EZ box, and ordering a AFE Proguard 7 today; I am looking at what to do to make the exhaust a little free’r flowing but not any louder than possible.



So here are my questions, is there a muffler replacement that will open up some CFM’s that doesn’t produce any more (or little more) sound than stock when normal driving?



Should I just skip the muffler idea and go with a whole new system later on?

If I do go with the exhaust route is there a down fall to the 5” system?





I want more flow, I don’t need the “most flow”, and I want to keep it fairly quite since this is our primary weekend family vehicle.



Thanks in advance,

Dave

If you read the TDR (and most of us do) you'll find the power writers say don't waste your money on a larger pipe unless you're going for power mods of 400 hp or more. T'aint necessary, especially when there're other toys out there beggin' fer yer $$$.

 

[Mad Bomber]

Stock or not

DM, that makes me lol EVERYONE thinks they will leave it stock.

 

[krabman]

The point where you will be able to see any gains on a 5" is well into 500 hp according to recent research by Don M. You can purchase the Banks downpipe separately.

 

[Jeremiah]

Precisely

Originally posted by krabman

The point where you will be able to see any gains on a 5" is well into 500 hp according to recent research by Don M. You can purchase the Banks downpipe separately.

My pernt, precisely, Krabman. I think $800 pipes are a waste of money and I appreciate the TDR writers for saying so. I know the dealers don't like to hear this (it hurts their business) but we're in the business of being honest with readers. That's what this forum is all about.

 

[JThiessen]

I have to agree that the cost/benefit ratio really isnt there for airflow improvments when considering only performance enhancement - especially if you are talking 800 bucks for one. I got my Banks for 625 incl. shipping, so for ME, the sound quality was worth the money. Now that I am actively looking at boxes, the airflow/EGT control will hopefully improve my "return on inverstment". I have put aftermarket CAT back sytems on in the past, and had them rust out in two + years time. I had no idea how long (or short) a period of time it would be until I started adding HP (I thought I had more willpower), so I wanted to start doing the preparation for the higher HP, and to have something that might last a little longer (Stainless).

 

[Jeremiah]

Incremental increases

Originally posted by JThiessen

I have to agree that the cost/benefit ratio really isnt there for airflow improvments when considering only performance enhancement - especially if you are talking 800 bucks for one. I got my Banks for 625 incl. shipping, so for ME, the sound quality was worth the money. Now that I am actively looking at boxes, the airflow/EGT control will hopefully improve my "return on inverstment". I have put aftermarket CAT back sytems on in the past, and had them rust out in two + years time. I had no idea how long (or short) a period of time it would be until I started adding HP (I thought I had more willpower), so I wanted to start doing the preparation for the higher HP, and to have something that might last a little longer (Stainless).

I understand. Once the bug bites, we shell out big bucks for for not much increase in power or performance. I've heard good things about the Monster Muffler sound. I just bought gauges, an EZ and a new washer and dryer. My wife supports the latter but doesn't know about the former. Gonna leave well enough alone.

 

[Detroitiron]

Last August I put on a 4" system w/see through muffler, along with the AFE Magnum Force air filter and box, and the next day I drove from VA to IN, a 790 mile, (one way) trip. Then I drove from there to VT, another 780 mile, (one way) trip, and then to points south and west for the rest of that week. After putting on the 4" exhaust, from turbo on back, including down pipe, and the humongous air filter system, I saw a real world measurable gain in mpg (2+ empty), and power, torque that you can feel with a low tech butt dyno. Pulling 11,500 lbs over the mountains, I roared right past everything in or near my weight/power class, and blew the doors off any 18 wheeler whenever I felt like it. To date, these are the only performance mods on my CTD. My system came from a vendor on eBay. It's not a "BIG NAME" brand like Banks, et al. , but it's aluminized steel and mandrel bent, came with welded on hangers in all the right spots, and cost just under 3 1/4 Franklins inc. shipping. Sooo, whomever said the bigger exhaust mods aren't worth it on an otherwise unBOMBed truck, I beg to differ, based on 23,000+ miles of experience with a 4" system. Maybe, since the '04's come with a 4" exhaust, the jump to 5" may not be worthwhile, but the jump from factory 3" to aftermarket 4" definitely is!

 

[Jeremiah]

The "whomevers" referred to are the technical writers for the TDR whose expertise isn't challenged. They say the 3 1/2" pipe on 3rd generations are all you need until you bomb 'em up beyond 400-500 HP.



But to each his own! Heck, spend that money! If it feels good, do it, I always say!