Your rotors would have to be reallyyyy warped to get vibration while coasting. Warped rotors are pretty easy to diagnose. At a faster speed, hit the brakes and you'll get more vibration compared to going slow, just slowly ride the brakes and you may get a lunging/lurching feeling. I guess my point is that warped rotors will vibrate based on speed/brake pedal pressure, where as bad bushings/ball joints may not.

Take it to a break shop, and you'll need brakes. Take it to an engine shop and you'll need a new motor. See the trend?

You need to find a good independent BMW repair shop that you can trust. Should be plenty in Chicago area.

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2002 X5 4.6is - Titanium Silver / Black Alcantara - Dinan Stage 2 - Bilstein/Eibach - Brembo BBK ----SOLD---
1993 318i - Brilliantrot / Tan - bone stock daily driver