Types of Motor Oil
Today's line of motor oils can be divided into 3 main categories:
Conventional motor oil
Conventional oils are the result of refining crude oil. During the refining process, crude oil is separated into many different elements. Some of this material becomes the basis for fuel and oil. Conventional motor oil is made up of a mixture of long and short chains of carbon and hydrogen atoms.
In extreme heat, short-chain molecules can evaporate and unstable molecules can oxidize. Conventional oils also contain more naturally occurring impurities such as sulfur, reactive hydrocarbons, waxes, and other unwanted contaminants that can't be completely removed by refining.
Full Synthetic motor oil
Fully synthetic motor oil is made from non-conventional, high-performance additives and fluids. Full synthetic motor oils typically use a base stock called polyalphaolefins, or PAO. Synthetic motor oils have a smaller, more uniform, molecular structure which makes the consistency and lubricity properties much better. Synthetic oils do not contain as many contaminates, such as waxes and reactive hydrocarbons, as conventional oil. The result is a motor oil that remains viscous under the widest possible range of temperatures and engine conditions.
Synthetic motor oil is better at preventing wear, it flows easier, keeps the engine cleaner, maintains its viscosity longer, and prevents rust better. Synthetic motor oil is usually considerably more expensive than conventional motor oils. But you can go much further between oil changes, which in turns saves you money. Plus you are using less oil in the long run.
Synthetic Blend motor oil
Synthetic blend motor oils are an attempt to get the best of both types of motor oils; the superior properties of full synthetic motor oil, and the lower price of conventional motor oil. And the performance characteristics are about where you would expect to find them, right between the full synthetic oil and the conventional motor oil. Most synthetic blend motor oils are not true synthetic oil, as they do not have a PAO base. Synthetic blend motor oils typically include a premium package of anti-wear agents and additives.