Dear Rayaan,8 years owning an RX300 and over 2 years of an RX450H without any sign of rust on both started me thinking when I discovered the rust and I will monitor progress and advise.
Dear Colin,My rust is the old fashioned brown in colour showing through the galvanising,so raises the question of whether it is external or internal but I trust the garage to resolve.For the wider community if this is isolated then so much the better or Lexus may need to take a closer look.