I have a 2004 GS430 with only about 18,000 miles, and recently started noticing noise while driving. With the windows closed and radio turned down, it's most noticeable. It's like a loud hum, almost like something is impeding the turning of the wheels. Sometimes when the brakes are applied, there is a little too much of a hum and/or slight grinding feel too. But the brakes don't even have to be applied to hear it. Anyone have this problem or know what it might be? Noisy rotors maybe, calipers not fully releasing? Thanks in advance.
