One problem related to brake disc pads has been reported for the 2000 Lexus RX300. The most recently reported issues are listed below.
Shortly after I puchased my vehicle I began having flat tires at 1200,1700 and 2018 miles. When the tires went flat, they were off the rim flat, due to the soft construction for the rubber for the luxury ride. The tire manufacturer was notified and the problem was remedied with replacements. At or around the same time I noticed problems with the brakes. Ie, excessive squeeling, popping and delay in stopping. I have made 4 trips to the dealer for repair consisting of lubrication, rear pad replacement, front pad replacement, replacement of brake pad hardware with the hardware replacement taking 2 weeks to repair and that was at 12000 miles. I contacted the dealer again regarding the brakes at 12913 miles. I also stated concern about the thin paint job on the auto and how many chips where on the car at which point I was informed that several customers where complaining about the paint on their cars.