We've been having this problem for a while. It has happened twice. The covers of the roof Rack falls while driving . We already bought a new one ( the driver's side). Today the drivers back cover fell while driving and we didn't even noticed. When we arrived home we noticed it wasn't there...It's very expensive to replace them. The one we already replaced cost around $110.00. This part does not have screws to the roof. It only snaps on...very unsecure...really a pain, costs and getting the part...