One problem related to coolant leaking has been reported for the 2011 BMW X5. The most recently reported issues are listed below.
The car is putting out white smoke. It seems as though oil is entering the combustion chamber and burning out of the exhaust. The oil is either burning or leaking into the fuel system. There is a significant decrease in fuel consumption and the acceleration is affected. As I was driving there was a warning that the engine has gotten too hot to drive and to pull over immediately and I had it towed to a garage. There were no temperature warning lights or coolant warning lights and coolant level was fine. BMW does not have a temperature gauge to know if your car is getting hot. Stupid design.