My 2003 LX470 always idled quietly, until quite suddenly at just under 16,000 miles I noticed what I would describe as a roaring sound (not really a vibration) when the vehicle was idling in gear. The roar occurs with engine idling at or just under 600 rpm. The roar is louder if you lean forward. When idling in park or neutral the vehicle is as quiet as ever, but the vehicle is also idling at higher rpm then. Is this what you guys are describing? I don't really notice a vibration. I just hear a mild to moderate roar that tends to make my ears feel stuffed up as I wait in traffic for the light to turn green. Hit the gas and we're back to normal. The dealer has ordered engine insulators and dampers along with exhaust dampers. Since I'm about to take off for a long road trip to south FL, I'd sure like to know that its not something more sinister.
