...sludge, and self destruct? These Camry engines between 97 and 2004 were know to have sludge problems. I have maintained it with regular oil changes, and now use synthetic oil, but it does get used for short trip city driving fairly regularly, with highway trips in between. It shows show no present signs of problems, and does not eat oil. It has 37,000 on it. Do I need to be worried about the deadly sludge, which destroys engines?