I have never found it necessary to do anything other than bled the system. That's what the bled screw is for. It is a closed pressurized system and coolant moves throughout the system. Trapped air is moved when the thermostat is opened and heater is on. It doesn't stay trapped. Air exits via the open bled screw. I usually bled it twice when I first fill it up but I can't remember the last time air came out the second time. If you are losing coolant, start looking for a leak.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas