Most of the noise appears to be transmitted to the shell from the rear "axle". If you look at quieter cars with a multi-link rear suspension design, the rear subframe is typically isolated from the shell by rubber bushes. It's the same story with a Focus, which is similar in design to a Mk5 Golf at the rear, yet the current shape mondeo and s-max which are an enlarged evolution of the focus rear are quieter and have a rubber mounted rear subframe.
The Golf / Octavia / A3 / Leon with the multi-link rear end are noisy, the only exceptions I've noted are the 4wd cars, which presumably have a rubber isolated rear subframe - mainly to avoid diff noise transfer to the shell, but with the added benefit of additional road noise isolation?
Anyone know if the Passat has a directly mounted rear subframe?
The way to make a Mk5 golf quieter is move to France and drive only on super smooth Autoroutes.
That said my car is much quieter on the winter tyres than GY F1v2.
