My dad’s driveway had a thick black oil stain on it from my old 4Runner… It being my fault, I felt obliged to try a few different methods to clean up the oil stain. After pressure washing the entire driveway I made a couple passes with hot water from a kettle, dawn dish soap, and a stiff brush. It lightened it quite a bit. Finally, I put the cheapest cat litter I could find at walmart on the top and then wetted it with a watering can to soak it without washing it away.
I came back two days later and the spot was gone. Really gone. It was a pretty rudimentary process, but it worked for me.
