Took my wife's 2010 BMW X5 in to diagnose a small oil leak. It was discovered that the oil pan and rear main seal were both lightly leaking, estimated repairs around $3400.00. The technician, Rob, also heard a whistle in the PCV system that I couldn't hear. Rob recommended we repair the PCV problem first to relieve any internal engine pressure. Total cost, $161.00!! It's been two weeks since Bristow's did the repairs with NO new drips on our garage floor!