[Richard]

Gregg asked for quantifiable data.

Here it is. With engine on high idle, in other words about 1000 rpm. dB reading in drivers seat 38 dB, reading two feet directly in line with exhaust tip, 85dB, and reading at the rear of the engine one foot away 85dB. All of this with a free app on the iphone, so perhaps not calibrated. But it gives an idea. I do not know what the readings would be with the stock Donaldson muffler.

My point is the S60 is a loud engine with noises emanating from the block.

I couldn't talk Rhonda into hanging out the bedroom window while I hit the jakes at 65 mph.