Hello, I am getting a gift from my Grandfather. A 1998 chrsyler concorde with infamous sludge making 2.7 liter. The car has only 51k very well maintaing 3k mile dino oil changes. I am driving it 1500 miles home. What would you do to car for this car? auto rx, synthetic oil. What is the best cleaning synthetic oil to keep this engine clean. any advise appreciated.