It's the original synthetic oil. I had a new 97 f150 I ordered when we returned from Germany with the military. I started using Castrol Syntec in it because I wanted to take the best care.. We because it was supposed to be better I started asking how long could I go on an oil change, and no one had an answer. I started asking around on message boards specifically the TDi Club (I had just bought a TDi at that time) and they guy named Terry Dyson chimed in and said AMSOIL was the best and that you could go one year or 25,000 miles on an oil change. I thought he was full of shit... Turns out he was into tribology. Tribology is the science and engineering of understanding these phenomena for interacting surfaces in relative motion. Basically a lubrication engineer. And he started sending me hundreds of oil analysis results with people doing extended drains with AMSOIL. I did a bunch of research and bought some for me truck. At the same time we had recently moved to El Paso and my wife was active duty, I had gotten out several years prior, so I was looking for a career, first I wanted to be a financial advisor, but the company I applied wit turned me down. Then I found out I could be AMSOIL dealer and do my own thing... I didn't have to ask permission. That was Nov 1999, I studied for about a month and got started Jan 2000 after the world didn't end... 23 years later I'm still at it and AMSOIL continues to manufacture the best synthetic lubes. Back then hardly no cars came wit synthetic, today virtually all cars are at least semi synthetic in order to get those low viscosity numbers like 5w20, 0w20, 0w16 etc.

AMSOIL is sold through a network of independent dealers which I'm one. We make products for cars trucks, boats, motorcycles, ATV/UTV, heavy equipment, two cycle etc.

https://www.amsoil.com/about/synthetic-versus-conventional/?zo=5027237

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