One of the most common questions asked of "tech experts" is: "What is the best oil?" Well, that has a major "qualification" attached to it. What exactly do you have in mind for it?

Spaghetti sauce, or motocross?

Entering any major auto parts store you will see a tsunami of motor oils of every description.  The only thing many of them have in common are the Federally mandated "SAE" and "API" labels. These are specifications set up by the "Society of Automotive Engineers" and the "American Petroleum Institute". These apply to oil's viscosity (how easily it flows, at different temperatures) and ability to stand up to heat and load. These "standards" have been around with minor changes since Hector was a puppy. Viscosity is measured by increasing numbers. 10 meaning the oil will flow freely at low temperatures, and 50 meaning it has to be heated to flow at the same rate. Multi viscosity oils (10W50) means the oil flows at an equal viscosity at all operating temperatures. Ability to withstand load is measured alphabetically. API Service "SA" means very poor, all the way up to "SJ" which means the product is equal to (or better than) the highest standards everybody in the API will agree upon for the time being.

Gauging motor oils by these standards is like saying that you are a pilot, because you can find the airport.

First the "why" of oil? What does the oil we pour into the crankcase do? (Besides deplete our wallet). Oil is the very life's blood of your engine. It is literally a "live or die" proposition. Oil provides two critical functions that keep your engine running. (Yes there are others, but they are secondary.) The first is to maintain a barrier between moving internal parts, (IE: piston and cylinder wall), and drawing heat out of the deep recesses of the engine.

Back in the days of early engine development, the petroleum industry was in its infancy. Gasoline was a by-product that was generally used as a cleaning fluid, and the best lubricant came out of the head of a Sperm Whale. An acceptable lubricant was found in the lowly castor bean. Castor Oil. It was inexpensive, and gave "some" internal protection to the engine. It also had a remarkable side effect on the driver (or pilot in the case of an aircraft). We all know what happens when we take a gulp of castor oil from a spoon. Now consider breathing castor oil vapors for a while, and the fact that roadside "rests" were even fewer than they are now.  You talk about driving fast and "lose" taken to the tenth power. You betcha!

Over the years, petroleum based oils (technically called "mineral" oils) became the primary engine lubricant. Up until World War Two engine oils were just refined versions of the crude that was pumped out of the ground. Not much in the way of "additives". They simply did not exist. As W.W.II progressed, and "speed equals life" became the order of the day, oil companies put their research departments on a war footing, and the result was a generation of lubricants that allowed aircraft, P.T. boats, and tanks to run farther, faster and higher than the enemy.

Germany on the other hand was finding its oil production facilities being bombed into scrap metal. About to see it's oil reserves exhausted, German chemists began to look at various vegetable oils, and how they could be adapted to service military engines. The leading candidate was "old reliable" castor oil. It was good, but not really good enough.  Then one chemist began modifying castor oil with various alcohols, and synthetic oils were born. They could be produced locally in very fundamental labs, they actually performed better than petroleum based oils, and because they could be produced by a "cottage" industry, were impervious to Allied strategic bombing. Vunderbar!

This was also the advent of the "jet" aircraft engine. In it's early form, jet engines had an operational life measured in minutes. Aircraft would be towed to the end of the runway to save precious operational time. Synthetic oils helped extend that operational life considerably.