It seems that oil sludge can kill the latest Toyota engines used in the RX300.
Closer investigation reveals that if the oil is not changed every 10K, it can sludge. I can comment that my engine has drank 1 litre of oil in the last 8000 miles….unusual for a Toyota block.
Toyota are not invincible and regular servicing seems to be highly important with gearbox fluid change in the RX being 30,000 in the manual but 10,000 in reality.
Still, you can rely on your Landcruiser to roam about Africa all day long without an oil change for years.
Toyota Blog 