Well, I recently put stacks on the truck. I had the truck straight piped and was very happy with it, but it does get quiet loud. I wanted to retain the loud straight piped sound, but quiet it down just a tad and give it more tone.

I ordered the Dynomax Bullet muffler from Summit and had it the next day. Got it installed, and man am I happy. Has a very sweet tone to it. It's a little quieter than straight piped, but brought me right where I wanted to be. Great muffler choice

 

I found on mine, that muffler made NO difference in sound, I'm glad it worked for you though!

 

I found as for level outside the truck it seems almost the same. However, inside the truck I can notice a huge difference. I can hear the turbo much more now. Also today I installed the *****'s Whistler, and now the turbo REALLY whistles

 

I ran one on my truck for a while it did what it was supposed to do it cut down on the noise alot inside

 

have one too. love it. cuts out the drone that you get at a steady rpm going down the road.

 

Yup, it's great. Specially with the stacks