Humming/Droning Noise

[GSD]

My 1998 Passat 1.9 TDI Sport saloon has recently developed what I can only describe as a humming/droning noise accompanied, occasionally, by a slight vibration felt through the steering wheel. This noise is most distinct at around 40mph but at higher speeds it also seems to oscillate a bit.

At first I thought that this might be caused by some new front tyres (Michelin Pilot Primacy), an out-of-balance front driveshaft which had its outside gaiter renewed recently, or perhaps a shot wheel bearing. However as this noise has been present for around 3,000 miles now I think that if the noise had been driveshaft or wheel bearing related then this would have manifested itself much more obviously by now.

The noise doesn't seem to be getting any worse and, in fact, sometimes it's hardly noticeable. It also seems to make no difference if the car is in gear or freewheeling.

Any ideas?

[meriafel]

I may not be able to help much except to say the I wouldn't think it is the driveshaft which I assume has been removed to replace the CV boot and had both the inner CV flange bolts tightened and the driveshaft outer splined shaft located fully in the CV outer joint. Try pulling the driveshaft out of the outer CV which should be impossible if located correctly. (I know of one which dropped out on a full lock bend some time after a main dealer repair!

Front wheelbearings last for ever and take an age to go completely and I understand it is quite difficult in the early stages to determine which one is the noisy one.

[karlosthejackal]

Had a problem like this on my old passat it was a 1998 model.

I too thought it was wheel bearing,so took it to my local garage to get it checked out.

Eventually decided it was a problem with the brake pads or discs so I changed them and problem stopped. might have just been a coincidence but could be worth a try.