I can remember a time when I had an old Oldsmobile Delta 88 with 162k on it that developed some shift issues. What I thought was amazing is that with a tranny flush/fill/gasket and a bottle of transmedic my tranny was fine until I sold it with 212k on it. Another time I had a Ford Taurus whcich had a tranny that would shutter and slip. Again I did the same thing and used a similar product maybe Lucas or something and it improved the shifting. I would never suggest using this stuff in newer cars NOR with cars of any REAL value. However, I am amazed on HOW and WHY they work. Does anyone know why this stuff works?