Several weeks ago I had the vibrations issue. Not only my steering wheel but also the pssenger seat was vibrating. Long story shor I took it into the Dealer and was told that my rear differetial was gone plus damage to the right rear axle. Thank God it is still under warranty or else that would have been a very expensive job. Hope that is not your issue.

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-2006 E53 (X5 4.4) Titanium Silver, fully optioned (sports package, premium package, navigation, ride height adjustment, panorama moon roof, rear climate package). Aero kit installed plus set of staggered 20s with Diamaris tyres.