Question for 4.8is owners EDIT: problem fixed
 

EDIT: My dealer finally located the source of the whine coming from my engine

During my 2nd service appointment yesterday, my local dealer discovered that the whining sound was coming from my alternator. With the new one installed, all I hear is the wonderful exhaust note.

I hope someone finds this helpful.

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Just wondering if fellow 4.8is owners hear a whining sound when driving around with the windows down. The whine is more prominent at higher RPMs or in Sport mode.

Local BMW dealer first thought that it was the transmission. However, after conferring with BMW they were informed that this engine has a whine to it.

Local dealer took off the belt and the whine went away. Once re-installed, the whine is back.

Thanks in advance for your feedback.

Hmm I have some sort a buzz but I couldn't call it a whine. New belt? They have stuff to put on belts to reduce noise.

I have a whine that comes from the front under 2000 rpm, it almost sounds like a supercharger, and then at cruising speed with the radio off you can hear it too (of course crusing speed is right around 2k in 6th gear)

With my local dealer claiming BMW said the whine is normal; they wouldn't replace the belt or any other components.
I'm calling another dealer tomorrow to schedule a second opinion. Update will follow.

Yes, I would describe it as being similar to the whine of a supercharger.
However, what I'm hearing gets very loud at high RPMs. After returning from a road test w/the service manager, he told the SA "it was loud enough to hurt your ears w/the windows down between 4K - 6k.”

Probably a vacuum leak somewhere.

mine also has this characteristic supercharger whine. It sounds "good" so I've never complained :)

The only things on this thing I find annoying are: steering wheel whistle when turning, and a chirp like noise when I have the fan on (esp with the vents turned on).

Im not sure what it is, but ive learned to block out the sound.

I havent noticed one but will keep an ear out