I think the xDrive variant will move with the front driveshaft disconnected. You can achieve the same thing by disconnecting the electrical connector to the xDrive actuator.

But not the pre-facelift version, those don't move with a broken or missing front driveshaft.

But even with the front driveshaft removed, the axles will be turning the front differential, so it can't be totally seized. Which leads me back to "this is weird"...

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David.X5
2001 X5 4.4i Sport
SOLD! at 160k miles