Why goes synthetic?
To be short. Well, Synthetic oil is more uniform in molecular structure. The purity is far more better as this is synthesize in labs. If you remember high school chemistry, mineral oil is a cocktail (mixture) of hydrocarbon. The synthetics claim " ...Special synthetic base stock blend and advanced additive package provides up to four times the wear protection of other motor oils. Reduces friction for quicker engine response and increased horsepower. Improves fuel efficiency ... ".
Conventional oils come from crude oil that is pumped from the ground. Crude oil is made up of a complex mixture of molecules that form chains and rings of different sizes and shapes. Long chains of carbon atoms produce a thick, viscous fluid that flows slowly. Shorter chains produce fluid that flows more readily. In an oil refinery, crude oil is separated into various fractions, into lubricating oils and fuels. Even so, small amounts of contaminants, such as sulfur and reactive hydrocarbons, cannot be completely removed from petroleum, and may end up in motor oil base stocks. All motor oils are made up of base oils and additives. In general, fully synthetic motor oils contain non-conventional, high-performance fluids. Synthetic blends usually use some non-conventional, high-performance fluids in combination with conventional oil ... http://www.mobiloil.com/USA-English/MotorOil/Synthetics/Why_Synthetics.aspx
1930's � Primarily used by the military. Synthetic lubricants helped keep oil from freezing in army tanks during World War II winters.
1950's � Jet engines appeared and synthetics really took off. Speeds, temperatures and altitudes increased. Synthetics met the challenge.
1970's � Performance in race cars continued to show the benefits over conventional oils. Synthetic motor oil debuted in passenger cars.