What is a motor oil?
Motor oil is the primary determinant in the durability of an engine. It contains two basic components: base stocks and additives. Base Stocks The base stock is the bulk of the oil. The base stock lubricates internal moving parts, removes heat and seals piston rings. Motor oil base stocks can be made from: 1) Petroleum, 2) chemically synthesized materials, 3) a combination of synthetics and petroleum (called para-synthetic, semi-synthetic or synthetic blend.) A petroleum base stock consists of many different oil fractions that form the final product. Generally, molecules of a petroleum base stock are long carbon chains that can be sensitive to the stress of heat and boil off at relatively low temperatures. Engine temperatures break down these molecular chains, changing the physical properties (such as viscosity) of the motor oil. The difference with synthetic base stocks is that molecules are uniformly shaped, which makes them more resistant to the stress of heat. Because AMSOIL Synthet
