One problem related to engine funny noise has been reported for the 2008 Lexus RX350. The most recently reported issues are listed below.
While driving to work heard a funny noise and oil light begin to blink. Found out engine oil cooling tube burst and leaked all the oil out and has caused motor damage. Lexus send a warranty enhancement letter just a few weeks before describing a problem with the tube and that they would inspect and repair. Waiting on Lexus customer care to assist. So far only 25%. Looks like a class action law suit may entail.