I recently had my cats cutout because the were clogged. Now that they are gone, performance has improved dramatically. The only problem now is the sound. It had a Flowmaster 40 sido, but it was WAY too loud. I opted for the Dynomax 17748 (20 inch body). The mellow sound is exactly what I want, but from 1900-2300 rpm, there is a "bapbapbapbap" sound. I had my wife accelerate the truck on the brake, hoping is was a rattling skid plate or an exhaust leak, but the sound is right in the muffler.



Any ideas what could be causing this? This may have been happening the whole time, but I couldn't tell with the cats on. It was definitely happening after the cats were removed.



Yes, I know that the cats will muffle that sound, but



1.)I don't have the $$$ to replace them right now.



2.) If it is mechanical failure, I want to fix it.



and

c.) No, there have not been any codes thrown.



Video and sound here... http://www.youtube.com/watch?v=se0QEVvZPko

 

Man I have no clue. I do know that's the rpm range that people have the problem with droning, but don't know if that has anything to do with it.

 

to me it just sounds like a truck with glasspacks

i think it just a case of more airflow in the muffler

 

Do you think a cherry bomb glasspack a few feet before the muffler kill that sound?

 

Sounds to me like that is just the muffler. I had a similar effect with my previous Flowmaster exhaust. I swapped them out for a pair of Borlas, and haven't looked back since.

 

it sounds like its just the muffler man, takin those cats off really lets out all the sound potential. -abgarza's idea would probably help if not fix it completely

 

Do you mean the cherry bomb before the Dynomax idea?

 

yea. any muffler added to his system should muffle it down enough to get rid of that rasp

 

sounds exactly like my old set up http://www.youtube.com/watch?v=oKYjE414zwQ stock into glasspack.

 

OK. Found a 26" Cherry bomb glass pack. I'll slap it on as soon as I get home and take another video. Hopefully all will be well after this.

 

Glasspack on and the truck sounds GREAT in a quiet kind of way. (No cats, cherry bomb glasspack in to dynomax super turbo) It has a deep, mellow tone, and I can have a conversation at any engine load!! I'll try and get some sound clips. I tried it just with the glasspacks only and it sounded good too! I can always whip off the dynomax and leave just the cherry bomb when I feel like making some noise!!! Thanks for all the help guys!

 

Exhaust leak my friend.......