NATURALS VS. SYNTHETICS SNOWMOBILE OIL

September 1988 - There has been a gradual rise in the use of synthetic oils.  Although synthetics are anywhere from two to five times as costly as natural petroleum based oils , they do offer some distinct advantages.
Because petroleum based lubes are refined from crude oil, they can sometimes be just that.  When oil is refined, it is heated and separated into different factions.  The lightest and cleanest factions are used to make gasoline and kerosene.  The oils collected for lubrication purposes are those that are heavier, have a higher thermal point and have settled near the bottom of the refining tower.  The same qualities that give the oil a higher viscosity (sticking ability) and resistance to thermal breakdown, are responsible for a certain amlount of carbon buildup.
Synthetics, on the other hand, are man made lubricants that can be custom tailored to specific applications.  With synthetics, a chemist is not confined to what nature has provided and therefore can produce a lubricant that has a high film strength and burns cleanly.  With petroleum based oils, the higher the film strength, the dirtier the combustion,