BMW Repair: BMW 330XI Rear end noise, bmw 330xi, wheel bearings

Question
From about 38MPH and up there is a howling inside the cab and a slight vibration. Sounds and feels like it's coming from the rear end of the car.

It's a deafening noise that seems to be getting worse. The car has 47k on it and I'm beginning to get alarmed that something may happen soon.

Any ideas? Wheel bearing? R&P?

Thanks in advance.

Answer
If the the noise changes with steering wheel(like going side to side)it could be wheel bearings.If it starts and continues it maybe a pinion bearing.Check your fluid in the rear axle to make sure it is full.If it was the ring/pinion the noise would increase and decrease with acceleration or load.Check the center bearing as well although it only has 47k the rubber could be ripped on the bearing mount.