omaharam

I have an 04.5 600. I want to install a muffler or cat back system. There are so many to choose from and so many opinions both bad and good about all the systems. There is a thread about someone complaining about the MBPR exhaust being too loud. There are also many replies saying that it is not loud.

I know I am wanting the impossible here, but what I want is better flow with AS CLOSE AS POSSIBLE to stock noise level. I do not want to be pulling a 9000lb camper 800 miles and here the truck doing its thing. As it sits with stock exhaust and edge juice on level 1, I don't even here the truck. On a steep uphill or from a stop it is a little audible, but not loud.

Can all those with a 600 and the MBRP exhaust (towing preffered) please let me know what you think. How about a 1-10 rating with the stock exhaust being 1 and open pipes being 10.

Also, has anyone just modified their airbox and dropped in a filter, rather than spend the dough on an aftermarket box?

Thanks for the input

Mark Craig

omaharam,

If you keep the cat in place the MBRP will be very close to stock levels except when you flat foot it! If you pull the cat it will be louder, not LOUD but louder. We have a 2004.5 here that has no cat and it sounds great. Call us if you have any questions etc we'll be glad to help you.

Mark @ DPPI

wilnis

I purchased one from Mark Craig, had it installed along with a SS turndown tip, and my wife and I cannot notice much if any difference in noise. We tow 8000# horse trailer every weekend, and 10,000# one a few times per year. I've done nothing else to the engine, except using the Diesel Kleen/Marvel Mystery Oil combo which has helped my mileage about 10-15%. We still hear the radio fine, no comments from our friends, and I think there is a change in the quality of the sound, but not much in loudness. I like it. Maybe a 2 at the most on the scale you suggested, even going up hills WOT. Bill

deezulsmoke

I purchased a kit from Mark, installed it and was suprised really, I honestly couldn't really tell any difference at all in sound. The only time you can tell a difference is when you really put your foot in it, but it is still really quiet as long as you keep your cat on.

Dorkweed

I have a MBRP exhaust on my 04.5. Almost as quiet in the truck as stock. I still have the kitty on the truck though. The only place that it is louder is if you stand back by the exhaust. It has just a little bit more throaty sound than the stocker!! I like mine. Pretty easy install if you want to do it yourself.

Lightman

Well I don't know what they changed besides adding the cat and going up to 4" pipe, but on my early 04 truck, the system is way loud. If stock is 1 and straight pipes are 10, I'd say my truck is at a 7 or 8. When you step on it, or are pulling up a hill with a heavy trailer, it is booming loud. While it sounds cool to me, it can be annoying at times. It's fun to stomp it with the windows down and hear it reflect off walls or buildings to the right, but it's downright loud, by almost anyone's definition aside from someone who say, works on hot rods all day...

Does the cat cancel noise?

RamWheelsBy4

The cat does cancel some of the noise. I know mine got definitely deeper and a little louder minus kitty. I have the Banks Monster muffler and it is just about perfect to me now.

marc03

at idle a 2
cruise 1
wot 5

it is louder than stock but not obnoxous. sounds very deep.

TAS05CTD610

how would I rate it.

Stock = 1
Running around town, highway = 2
Running it pretty good (2500rpm shifts) = 3
Running WOT 4

I've run without the cat and it gets very loud, like you said problably a 9.5 (since the muffler is still there) It's not that loud. I've pulled a 4000lbs car on a 1000lbs trailer, and the fianc`ee slept the whole time (so it's not that loud) if you take the kitty off, it'll be loud. i agree with everybody here, sounds freaking awsome, but it's very loud, towing with it, forget it, long trips, forget it, it'll rattle your teeth loose, sounds great though. I'm actually looking at making a cut out that will bypass the cat, but dump back into the exhaust for off road, pulling and when I want it loud, but keep the cat for quiet times.

gipsl67

I think it has a deep sound. Not loud, just a little louder than stock. It sounds the same as stock at idle and maybe a 5 at WOT.

Hunter11

I am in the same boat as Lightman. Everyday driving it is no problem at all, sounds really nice. Hitch up the 5th wheel and take off for a trip and it is down right loud under accelaration. We have decided not to do anything to it until our next trip with the trailer but I may end up installing some kind of small resonator to help mine. I do have the Cat in place.

TAS05CTD610

Mark may have guess right if you check out your cat. That seems odd that it's really that loud for you towing, cause mine isn't that loud. Mind you the wife can sleep no problem towing up a hill (actually towing, and passing up a hill after a guy in some car ticked me, and I had to smoke him up the hill (sooty too)) You may wanna check your cat, from the sounds of it, maybe it's not there (insides) or somethings wrong with it. You could also try a donildson or something (spelling) I know a lot of people run those.

Lightman

A lot of this may have to do with age and how good your hearing is honestly - no offense to anyone. I have exceptionally good hearing, and maybe that's why I find it so loud, but there is no doubt that if I step on it, anyone that's standing outside will turn their head to hear what that loud engine is going by...it's the dead opposite of discreet..thats for sure.. Sorry Mark, I don't mean to rain on your sales cloud, just being honest - my system is booming loud when you step on it. For a point of comparison, WOT it is louder than my tahoe (5.7 v8/350) with dual flowmasters.

TexasCTD

Ive been pondering this exhaust decision for a quite a while now. I am torn between just cutting out the muff and leaving the kitty only.......or putting on a straight through type muffler.

I want a Deep, Deep sound.........with a little extra volume, but not much.

What i DONT want.....is to make my truck sound like a V-6 Gasser with duals. I cannot stand that sound.

I am leaning toward leaving the kitty and replacing stock muff with Donaldson or Nelson straight through muffler...and long....like 51".

Any thoughts on this?

Hunter11

I was thinking about this on the way into work this morning and started wondering if maybe the muffler would still install right if it was installed backwards. I installed mine with the hangers pointing forward like the stock muffler came off. The spiral inside points to the rear. There were no directions with the system so I just installed it like the old one came off. First will the muffler go on either direction and if so would it be quitier with the spiral pointing forward? Probably to late now for mine since I have clamped it down.