Our Dura-Seal® Hi-Strength Oil Stop-Leak is manufactured to be smarter than other brands. Our Dura-Seal® Oil Stop-Leak doesn't thicken your oil, so theres no risk of increasing oil compression. Instead, our oil stop-leak actually causes all the oil seals in your engine to expand back to their original size. Our method, doesn't effect your oil in any way. So you can use it in any type of engine, (gas or diesel) and any type of engine oil including; regular, synthetic, and even rotella!