I just purchased a 1995 Saturn SC2 5 speed. Was owned by 2 previous older gentleman and the car is in great shape ( mechanically and cosmetically). It has 155k miles on the engine and has only been drinking good ol' dinosaur oil. Now from what I've been reading, switching to synthetic will help clean up some sludge that has been built up and give this old mama some vigor. My father who is mechanically inclined but kind of goes by old wives tales, believes I should not make the switch. From various forums I've been on ( For saturn motors) experienced drivers are saying it is beneficial. I'm hoping to receive some feedback on this and possible some factual evidence of if it is good or bad. Thanks in advance.