Wheel Bearing Or Brake Pad Noise?
 

I've been trying to identify the whistling noise coming out from the rear of the car, but I'm not sure if it was the Brake Pad that is making noise or the wheel bearing. The whistling noise is more obvious when at low speed (5mph rolling even when I didn't step on the brake). So Far I have about 90,000 miles on my X, and using the Akebono Euro Ceramic Brake Pads (low dust) for a while now.
Does anyone know the part number for the wheel bearing with the hub? It this very common for the X5? I noise is also getting louder as days go by. thanks :thumbup:

A typical wheel bearing noise is more of a "ruh-ruh-ruh" than a whistle. It varies depending on road speed, and has a particular frequency that identifies it as likely to be a wheel bearing. Hard to describe here, but a mechanic who listened to the noise would be able to say if it sounded like a wheel bearing or not. A noise described as a whistle doesn't fit that, IMO.

You can see all the parts at www.realoem.com

Worth a try, turn off DSC and see if the noise goes away.
I had new brake pads one time and during cornering mostly can hear the whisttling but not with DSC off.

That whistling your hearing is coming from engine. Does it sound like a turbo whistle? It usually kicks in at about 1800 RPM

Hey SiLvX5, I am so glad you asked this question because I was beginning to think I was the only one who had this problem. I recently have started questioning if it may be the transfer case. Let me know what you end up doing

Sorry for hijacking. But i do hear like turbo at 1800rpm whistle. So what is cure?

Is definitely not from the engine, it sounds just like the brake pad noise. I will check with a mechanic and keep you guys update.

Any developments here?Was it the pads??

Wheel bearing noise is usually isolated to one side or the other. Do some 360 degree turns and listen. You'll know which side has the bad bearing if it is a wheel bearing.

Does it sound like whistling, or more of a metallic, rattling sound that is noticeable when traveling over bumps and uneven pavement?

If it is a metallic rattle, then it could be the inner brake pad rattling in the caliper. There is a three pronged clip affixed to the back of the inner brake pad that holds the pad in the caliper, and if that clip loosens/breaks then you will develop a super annoying metallic jingle/rattle coming from the wheel.

The loose brake pad clip is easily diagnosed by coasting about 10 mph over uneven pavement with the windows down. If you hear a metallic rattle/jingle, very (VERY) lightly press on the brake pedal while still moving, and see if the rattle/jingle stops. If so, then it likely is the loose inner pad.

If this is your problem, it’s easy to remedy. Just pull the wheel, open the caliper and pull out the inner pad. Gently pry out the three clip prongs on the back of the pad (or replace pad if clip is broken), and snap it back into the caliper. It should fit really snug into the caliper now, and not rattle.

This is pretty common problem with BMWs, and I have seen it on my X as well as an e30 that I had.

(Edit: This is kind of an old thread, but hopefully my post can help someone else having brake pad noise if the OP has resolved the problem)