Over the past little while, my BMW E39 has developed what I'd call sticky steering. It no longer self centres properly. If you were to put on a small amount of lock and take your hands off the wheel, it would go round in circles. It hasn't got any heavier, and raising the front end shows no obvious friction, although I haven't yet disconnected the track rods to see if both sides turns equally easily.
Just wondered if anyone had come across this, and it was some form of common fault.