Whenever you experience staggered lowering or raising of automatic windows, the problem is most often a faulty window regulator. For the BMW X5, replacing the window regulator is a rather involved process but one that can be completed. Here are the steps for how to change a BMW X5 window regulator
How to Change a BMW X5 Window Regulator
Remove the weatherstripping attached to the door and the window.
Remove the door panel with the trim panel tool. This removal can be done by prying the inner panel from the door.
Unhook the cables that enable the lock to work.
Remove the sound insulation from the door. This can be done using the trim panel tool.
Lower the window until approximately 6 inches of glass is left above the window's lower opening edge.
Remove the window. Twist slightly and lift the glass upward toward the top and rear of the door.
Remove the window regulator. With pliers, remove the nuts at the rear of the regulator and pull the regulator from the door panel (back to front.) Disconnect the cable attached to free the regulator fully.
Detach the window motor from the window regulator. Connect the new regulator to the motor. Attach the regulator cable to the new regulator.
Replace the window regulator by feeding from front to back. Replace the nut holding the regulator in place.
Replace the glass of the window onto the regulator. Tighten the window mounting screws.
Replace the sound insulation. Use Butylene tape to adhere the insulation to the inner panel.
Reattach the weather stripping and reconnect the door panel. Raise and lower the window to confirm a successful window regulator replacement.