i have a similar noise problem on ls 430 , which i started noticing after just 5000 miles .the noise is a whistling noise ,which starts at 25 mph.the car has 12000 miles now. this is not a tire problem , as i hv replaced the original dunlop sport with michlen energy ,still noise persists . i hv gone to two different lexus dealers several times ; hv spoken to lexus customer service umpteen number of times ,but of no avail . i am extremely frustrated with the after sales so also the noise .any suggestion to fix the problem ?