Hi, I've started to get a loud rumble noise when slowing down on the brakes in my e61 530d 2005, I don't tend to hear it if I'm driving nice and steady but if I open the car up and take it up to 80-90mph then hit the brakes to slow down for the roundabout the rumble is loud and can even drown the sound of the radio out. I thought this could be a wheel bearing but then puzzled me as to why it only does it when I'm on the brakes and only from above 80mph. Could it be noise from the brakes if they're getting too hot (possibly ready for a replacement) or could it still be a bearing? Or the diff even? The noise does sound like it's from the rear but I could be wrong as it can be that loud that it's hard to try and work out exactly where it's coming from. Thanks

 

Sounds like you need to get the trolley jack out and do a bit of investigation yourself

To start with I would jack each wheel off the ground and give them a spin, listening for any unusual noises, and check the wheel for any lateral movement (Bearing play). Then remove the wheels to check for brake pad wear!

Let us know how you get on

 

Maybe a pad fell out and you're stopping with the pistons of the caliper?

-r

 

I am having exactly same sound as you described. Could you please tell what was your problem brakes or wheel bearings? I using OEM M5 drilled rotors.
Thx