Taking a turn at full throttle my A4 suddenly became much louder yesterday. Upon inspection, the exhaust tube completely separated from the flange that holds it to the exhaust side of the turbo. The flange itself is still securely fastened to the turbo. Examining the turbo exhaust tube, I could not find any indication of previous welding. I'd assume it is supposed to be welded to the flange, no? I'm at 51,000 miles. Warranty just expired. Hope they don't give me too much grief. Might this be instead covered under the (US) 100K emissions warranty? Anyone else have this happen?