I drive a 2005 X3. The issues so far, sunroof shade got stuck once, replaced under warranty, passenger seat recall due to problems with passenger detection and airbag module, driver seat leatherette deformation which is found to be common in extreme cold weather locations and was replaced under warranty. Other than that if you drive the car coming down to flat road from an incline and it tends to hold the lower gear for a tad longer, there is a s/w patch for that which does work. Overall 2005/2006 are the best years for an X3. Good luck with your purchase.
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