One problem related to engine cooling system has been reported for the 2007 Lexus RX350. The most recently reported issues are listed below.
The oil cooling line in my well maintained 2007 RX 350 blew apart without warning, causing all oil to be lost from the engine and catastrophic engine damage totaling thousands of dollars were it to be repaired. This is apparently a very common, well known issue in the 2007 era RX 350 due to Lexus' choice to use a rubber cooling line. This occurred with no warning whatsoever.