As in past threads, some of us have had the "chuffing noise" when our 48RE's shift into OD. When I first heard it, I thought it was the tranny blowing apart. It only did it when I was going up a hill and giving it a lot of gas. Some folks piped in stating that it was not the tranny, but back pressure through the turbo caused by the sudden drop in rpms. A couple guys advised to remove the silencer ring from the turbo. OK, so I removed the the silencer ring and sure enough, no more Chuffing Noise......Turbo sound really nice too.....

 

I think someone was going for a buyback because of this noise. Wow easy fix. And yes the turbo sounds better with it out. ;D