I have had terrible vibration problem with my F06 on 20 inch OEM wheels since buying it in April this year. Got so bad every now and then that I was convinced a wheel was coming loose so I stopped to check them.
I had the wheels balanced 4 times. I replaced all 4 tyres (Bridgestones). I replaced the front disks and pads (Zimmermann's). But the vibration still there.
The vibration wasn't constant. It came and went every 20 or 30 seconds, but never stayed the whole time. I researched and spoke to "pros" and they said if it comes and goes it would not be tyres. They said it would be bearings, bushes, ball joints, engine mounts, suspension components or prop shaft. But not wheels / tyres....
So, I learn't about road force balancing. Had that done today at The Tyre Shop in the UK (highly recommended ) and have driven 70 miles and not a single vibration. The car drives spot on. £95 well spent, even though it seemed a lot for wheel balancing. BMW want £90 for an hours diagnostics.......
Hope that helps others. Bite the bullet and give it ago before replacing components.
http://www.balancemycar.co.uk
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