I replaced my up pipes with the single piece because I was too dam lazy to see if the gaskets were even leaking. Well they werent and I still have the same sound in cab. I had small load(1500lbs) on and with a 60 MPH head wind I heard it alot. I had my tow tune on and it got even louder and EGTs were rather high... Its about when you shift into 3rd or 4th a loud rush of air that bursts, than quiets but still says vocal... I might go grab a video... Wastegate is D/C'd also...