what's up boyz, I'm a newbie and I enjoy your conversations regarding our cars. I just bought a 2000 Gs 300 and I'm am experiencing that sound. I think it has something to do with the AC clutch. in my expeireince, I only hear the noise when the the AC button is on and I hear mostly at Idle, stop light or at low speed. I'm taking the car to the dealer ship next week. I'll keep you up to date.