I have an 02 Silverado with the 5.3. I'm running a flowmaster muscle truck catback. It consists of a 3" I-pipe into a super 40 muffler with a 3" inlet and two 2.5" outlets that exit in 3" chrome tips in front of the passenger side tire. At first it sounded awesome, it had a deep, clean, throaty sound I absolutely loved. After it was on the truck for about a week though it seems to have quieted down a good bit. It isnt as deep or loud inside of outside of the cab.

I had planned all along to have the system welded to ensure a leak free fit so I went ahead and had it welded up at the inlet and outlets of the muffler thinking maybe I had an exhaust leak. This doesnt seem to have helped much as it still doesnt sound right. I got to thinking of how much deeper exhaust systems sound with a good CAI setup so I replaced the air filter to see if that would make a difference. The filter that was in it when I bought it a month ago was nasty. This seems to have helped a bit but it still doesnt sound like it used to.

What else could it be? Is it possible I have a leak where the I-pipe connects to the stock y-pipe that I cant hear? I'm about to start the truck in my garage and lay on the floor on the passenger side of the truck to see if I can hear anything.....Is there another way to identify a leak? What else could cause this? I suppose it could be my imagination since I'm used to the sound now but the difference seems huge.

No anti flowmaster crap, please. This is my cruiser and they make the only exhaust system that has the sound I like. Thanks.

 

This is your problem right here

Sorry I couldn't help it but you'll find most people on this site hate Flos, including me, and will be reluctant to help you. The way you describe the problem doesn't sound like a leak. A leak will have an almost ticky sound in the cab, it just sounds like you don't like the way the system sounds. Look for black discoloration around the seams in the system to spot a leak. Other than that try shortening your tailpipes for a deeper sound.

 

Maybe the tone changed once there was a little carbon in the muffler. If you are not happy with the sound, you can change just the muffler.

I have had Magnaflows and Hooker Aerochambers on my truck. Both sound awesome. I had the Magnaflows when I was N/A. I put the Hooker on when I went Turbo.

 

I didn't ask for your opinion on Flowmaster. Thanks for the suggestion, though.

I love the way it sounded, its not that I dont like the way it sounds. The sound really seems different. I thought about carbon build up but thats never happened to me before.

I've had magnaflow, hooker and dynomax mufflers on other vehicles. All sounded nice but none sound as good as the super 40 on my truck. At least the way it did sound, or the way I imagined it sounded..........Hell maybe I'm crazy.

 

Is this your first Flowmaster? I know the set I had on my last truck changed once they "broke in".

 

sounds like the flomaster is breaking in

You could always go with a shorter case length

 

Ive Had Atleast 3 Different Flowmaster Mufflers On Different Vehichles, The One I Used To Have On My Truck Was A Super 40series 3inch Single In/out Dumper Bafter The Axel, I Loved It But It Got Too Loud After A While So I Went To A Bassani, Now I Have A Bullet 3inch.i Like The Sound Of Flowmasters, I Think Your Problem Could Be Maybee The Passengers Side Donut Gasket On Your Y Pipe To Your Manifold Could Have Came Slightly Loose Over Time,so Check That. I Would Replace The Single In Dual Out Muffler Iwth A Single 3inch In/out Design Youll Prolly Like The Sound Better And Itll Give You More Torque, Thats What I Had On Mine And I Loved It, Awesome Sound.

 

i have the same setup on my truck if you do a search you can hear it how it sounds with the 6.0 and no cats with headers. when i had the 5.3 it sounded good. give it time it will get louder again

 

STFU already about flowmasters, untill anyone on any site can prove them wrong then ppl shouldnt open their mouth about them. ppl love the bandwagon and why you get ppl like yourself. this isnt a personal attack its a statment to everyone who down grades these setups untill they can prove it, they shouldnt speak

 

qwick is so right. Ihave used nothing but flos an my 5.3s and It sounds alot bettre than a magnaflow glasspack<thats all a magnaflow is. I do think that JBA makes some awesome stuff too though log on and hear that beast of a LS1