Hi All. Newbie here, just came from a test drive of a 2006 A3 2.0T. All was well, except I noticed a very loud boom noise at 20 - 40 mph. This was especially magnified if I lifted throttle somewhere in that speed. Hard to describe the sound - I think boom is the term used in automotive circles. Like a loud echoing roar but without any clunking or distinct individual sounds. I didn't get a chance to take it much higher speed than that, but it did seem to be quieter at 45 mph.

This car had 92k miles on it. Couple of weeks ago I test drove a 2009 A3 2.0T with about 70k miles and didn't notice this sound.

Just curious if anyone has an idea what could cause that, and more importantly is it something that can be easily taken care of (e.g., with a tire change - this car did have some aggressive looking tires but not sure if that alone would cause such a noise at a specific speed).

P.S. I'm in the USA. Not sure that matters, but the car is spec'd for US market.

 

Could be a bad bearing on one/more wheel hub's. I had same issue and mechanic said that's bearing issue.