Synthetic oil is something you do for life. There is no switching in and out when there's a sale. If you switch back and forth, you'll develop leaks due to rotting seals. QUOTE]


Agreed...I changed to synthetic on a 93 cutlass with over 100k miles. Soon after started developing minor leaks. As mentioned, deal or no deal this is something I would only use on a new car and stick with it...Jack