XSeries-forum

Noticed today when driving slowly with the windows down that the car is making a funny mettalic whirring/ squealing noise when driven. The noise is related to vehicle speed but much faster than wheel rotation speed so I'm thinking driveshaft related? Seems worse when off the gas/ decelerating than when applying throttle and goes away above a certain speed like 20mph, although the road noise etc could be drowning it out.

Also seems to thud slightly now and then when turning / maneuvering at low speeds, feeling a little like an engine misfire for want of a better way of describing it. Is this my transfer case gone south?

I get a very feint whining which I notice more when gently coming off the gas at low speed (20-40). It annoys and concerns me but my wife can barely ever hear it (when I'm asking her - can you hear that noise). Has been doing it ever since I had the car (3 years) and nothing has exploded yet so I don't think about it anymore.

Turns out this is due to failed bearings in the UJ on the front propshaft - something BMW supposedly check in a "quality enhancement" (not a recall) and replace if required as per the sticky post. Mine was apparently good enough to not be replaced when it was checked 16 months ago but now is kaput due to rust and the bearings are shot.