1997 525i
I have a groaning sound coming from one of the rear wheels.
When the speed gets above 40mph the groaning starts and gets slightly louder as i increase speed, the groan sound gets faster and louder the more speed i do. I think that naybe it's the bearing but it does not go quiet on corners when i unload the weight??

Hi, Deedee-
The fact that it gets higher and louder as you increase speed makes me think that it is indeed a bearing.
On Hondas, a bad wheel bearing makes a whum, whum, whum sound.
I don't know what it sounds like on a BMW...not yet, anyway.
Good luck.
Flunky
PS-Bad wheel bearings make noise all the time the car is in motion, no matter whether you're going around a corner or going straight.