I had an old 2001 F250 Superduty with a 5.4 liter engine and 230,000 miles which caused antifreeze to seep into the oil pan because it looked like it like a root beer. Was going to write off the car but decided to give this product a try after it was mentioned on a TV show. After trying all 3 products and "air drying" the system overnight I can proudly say the leak is gone and my crankcase is clean. Although I should have used it sooner (when it worked its problematic condition caused a slight knock in the morning) I drove a truck and had no problems. Just follow the instructions exactly as directed. I'm a believer now!