Hi everyone I would appreciate some help with this very annoying issue. 2006 Audi A3 2.0 tdi Quattro s line Between 70 and 80 mph i get a very deep vibration noise through the car. It goes away after 80 and does not come in at low speeds. No vibration through steering wheel. Its just a very deep bassy resonating noise which you can feel. I have been to vag audi specialists they cannot find the fault. Awsome GTI manchester have checked the car. Done all the usual balanced wheels etc. I even bought a brand new set of alloys with new tyres and re-bal still no joy. Has any one else come across this issue, or could point me in the right direction im trying to avoid main dealer. Myles - if any one can help genuine i will quite happy send a full crate of beer lol.