One problem related to radiator hose has been reported for the 2009 Lexus RX350. The most recently reported issues are listed below.
The oil cooler manifold which has rubber hoses leaked completely out. The new parts have a solid metal hose, not rubber! I believe Lexus obviously knew the rubber hoses were a cheaper method of cooling, though they are "high pressure" and should have been metal at the time of manufacturing the vehicle! I have seen blog after blog of people with the same issue. Oil all over my driveway and again, I believe the motor has been damaged due to driving home (unaware there was an issue) until I saw the oil everywhere underneath and on the side of the motor.