I felt a vibration, like a tire, but it persisted. I called the dealer, who was booked for a week or more. A couple days later the front driveshaft broke, hitting and cracking open the transmission and oil pan like an egg, I now find that cars manufactured from April 2011 onward were recalled for this issue. Mine was manufactured in March. Mine had the transfer case replaced and yet no one mentioned the U-joint going bad or the recall. Shortly afterward it failed. BMW denies any responsibility. If anyone has a 2011 X5 and feels a vibration, take it straight to a dealer. Do not drive it. I wish someone had warned me. This could be a life threatening issue, not to mention a $12,000 repair.