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Posted
I have dynomax ultra flo ss mufflers on my 1999 6.0l and would not trade the sound or performance for any of the previous mufflers I had on ( flowmaster, magnaflow ). They are the offset inlet and center outlet part number 17289, quiet up to 3000 rpm's with deep powerful sound after 3000 rpm.

 

What performance gain did you see?

 

 

I got .2 seconds reduction on 0-60 on my G-tech meter, this is going from a single large magnaflow 22" case lenght with two 2.5" inlets and one 3.5" outlet to the dual 2.5" Dynomax mufflers. The funny thing is that it's quieter too and a more refined deep sound than a loud raspy sound.

 

 

Ok, thanks.

 

Anyone measure the back pressure of the stock system?

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Posted

now im more confused n what to go with after reading some of these posts I was going to go with the flo pro but your right sound is just raspy bad. I wish I could afford the borla id be all over that bad boy, i am now leaning towards flowmaster, just not sure which one to go with, like I have said before I don't want wake the neighbors loud, just a nice deep rumble.

Posted

your neighbors are still going to hate you as I hate the idiot down the street goes past my house at 50 mph every morning at 5 am with his duel exaust dodge hemi. LOL,He works weekends.

Posted
your neighbors are still going to hate you as I hate the idiot down the street goes past my house at 50 mph every morning at 5 am with his duel exaust dodge hemi. LOL,He works weekends.

 

yeah but im not gonna be going 50 down my 25mph street

Posted

I have an '03 6.0L. The factory exh. was junk! Failed at 50kmi.popped spot welds some type of internal restriction.Horrid fuel mileage!12mpg. installed a Corsa Sport...Easy install(same as GMPP)Fuel jumped to 18+mpg sounds great,couldn't be happier!It is pricey, but I got an Epay deal at around $300.(?) shipped.Paid for itself quick with the extra 6mpg!

Posted

I just have a 2000 5.3 but the Gibbsons I have is awesome! Quite at low RPM and nice and throaty at high. It coast more but I get 2-3 more MPG and its been on my truck since 2001 with no cracks or brakes in it. And you don't hear it at all on the high way.

I would say Gibson or Borla. . . There is a reason they coast more. But Don't get me wrong. . . back when I was younger I loved the sound of Flow master. And if its installed rite its an awesome way to go. If you don't mind the deep loud throatynes of it.

Either way it just depends on what you want. . . Deep loud, Throaty with Flowmaster or Quitit tell you want it with Gibsons or Borla. You just have to hear um all.

And as long as you have it installed rite. It should last.

Posted
I have an '03 6.0L. The factory exh. was junk! Failed at 50kmi.popped spot welds some type of internal restriction.Horrid fuel mileage!12mpg. installed a Corsa Sport...Easy install(same as GMPP)Fuel jumped to 18+mpg sounds great,couldn't be happier!It is pricey, but I got an Epay deal at around $300.(?) shipped.Paid for itself quick with the extra 6mpg!

 

You swapped from a stock exhaust to an aftermarket and your MPG went up 50%.

 

Right.

Posted
your neighbors are still going to hate you as I hate the idiot down the street goes past my house at 50 mph every morning at 5 am with his duel exaust dodge hemi. LOL,He works weekends.

 

I recommend they have the pipes exit into the cab so they can roll the windows up when they need it to be quieter.

Posted

well im going tomorrow to get my exhaust done, im gonna go with the flowmaster not sure what series yet, ill get a sound clip up once its done, its one of those things im a little nervous about, its gonna suck if I dont like how it sounds, wish me luck guys

Posted
well im going tomorrow to get my exhaust done, im gonna go with the flowmaster not sure what series yet, ill get a sound clip up once its done, its one of those things im a little nervous about, its gonna suck if I dont like how it sounds, wish me luck guys

 

Got it done sounds awesome went with the 40 series the black one kinda loud inside at low rpms but ill get used to it...it sounds great outside the truck.

Posted

I put the gibson on my NBS 2500Hd 6.0 and its great! not too loud no drone at crusing speeds.... I emailed flo-pro and the part number for the nbs 3/4-1 ton is 2510 they said it was the direct replacment with a performance tone and no interior drone

Posted
I put the gibson on my NBS 2500Hd 6.0 and its great! not too loud no drone at crusing speeds.... I emailed flo-pro and the part number for the nbs 3/4-1 ton is 2510 they said it was the direct replacment with a performance tone and no interior drone

 

What is a performance tone?

  • 3 weeks later...
Posted
This is the first 2500 HD I have every owned and would really like to put dual exhaust on it, but was wondering what the best exhaust for the money would be? BTW it has the 6.0L. I really like the way it sounds now, not extremly loud, but you can definately hear it.

 

I would like to pair this up with a cold air intake, but not sure if doing either of these will void any warranties?

:cool:

hello there l have a 2006 hd sierra, what you truck guys are missing is that when your catalytic converters plugup your exhaust is not working very well,l'm thinking of magnaflow catback system,l know there is some cutting of the pipes but they don't offer what l'm after,so look's like l'll be cutting some of pipe no problem.l know the sound will come out great!don't be scared to change out your catalytic converters too.l had a 97 chevy sliverado and change the cats with new flow-master big differance.sold the truck milage was high sorry to let go but l'm happy with my new beast.when add cold with exhaust you will notice a big differance in power!there is no need for power chips or programers you can achive stock power with exhaust and cold-air intakes.

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