STP High Mileage Oil Treatment + Stop Leak - 15 FL OZ Protect the engine in your high-mileage vehicle with STP High Mileage Oil Treatment + Stop Leak. Formulated especially for vehicles with over 75 000 miles this high-viscosity engine additive includes ZDDP oil additive as an anti-wear agent for extra protection. This STP oil treatment creates a thick cushion between moving engine parts to help fight metal-to-metal friction. Engine stop leak helps to rejuvenate seals and gaskets and stop engine leaks noise and smoking to improve the performance of your high-mileage vehicle. Add this treatment to your engine oil with each oil change during regular car maintenance. It s suitable for all cars light trucks and SUVs.