I was made a believer in Slick 50 the other day when I was talking to someone at the auto parts store that said that they had an S-10 with almost 300,000 miles on it. He had used the additive since the day that he purchased the truck. I was shocked! I had never heard of a domestic car going that long. I was reading about my car and according to Volvo it is not recommened that you use additives because of the turbo. I would really like to use this stuff if it works that well. Being that Slick 50 is just like heavy gear oil anyway, do you think that it would do any damage? Anybody using any additives now? (Slick 50, Restore, STP, ETC....) Thanks!