I am looking at buying an RS4 finally...its a 2006 model with 60,000 Kms on the clock. Other then the milage the car is like new.

The only thing i though was suspect when driving the car was a whining noise that could be heard when letting the car coast down the road at about 20kph. (not braking or accelerating)

Anyone heard of this before???

 

I have an '08 and I haven't noticed anything like this on my car. I'm thinking maybe you are hearing the Quattro system possibly....?

I'm assuming it was in gear when coasting down the road? If so, these cars make all kinds of cool mechanical noises.

 

Transmission noises such as this are most likely the result of worn diff bearings, a worn pinion bearing, or problems with the pinion/ring gear.

Try coasting in different gears with and without the clutch engaged, and see if the noise changes relative to the clutch being in or out and the gear. Also try to put slight pressure on the shift while in a gear and see if that changes the noise.

It's possbile that the noise isn't coming from the transmission at all and can be a wheel bearing, which can be diagnosed by turning on a curve at speed (safely) if the noise increases then the wheel bearing that is being loaded is bad.