What Is Motor Oil Made From?

There are two different types of motor oil available today, synthetic oils and mineral oils. Mineral oils are the traditional kind derived from crude oil. In simple terms, crude oil is formed underground in rock formations and is the result of organic life such as plants, animals and plankton from the seas decaying in the absence of oxygen (usually due to a covering of mud).

Without oxygen the organic material decays into carbon compounds. Over time the trapped carbon compounds are compressed and transformed into crude oil by the pressure and heat from the surrounding rocks and new layers forming above. When the crude oil is refined into petroleum, motor oil is a by-product.

Other chemical compounds are added to the oil to improve its ability to reduce corrosion, clean the engine and maintain viscosity at different temperatures. Mineral based oils can become too thick to flow around the engine with sufficient ease in cold temperatures.

If you see you oil pressure gauge light come on this can signify the pressure is too low because the oil is too viscous. The oil gauge light can be triggered for many other reasons, some of which are explained in details at the oil pressure gauge guide blog.  On the plus side mineral based oils are cheaper than synthetics.

Synthetic oils were developed during the Second World War as a response to the problems of mineral oils solidifying in the cold temperatures on the front line. Technically speaking synthetics are not derived from a petroleum base and the raw materials used in their production can vary.

But in reality, for consumer motor oil products, a petroleum base is still used. During the synthesis additional additives are included to change the properties of the oil.

Synthetic oils maintain their mechanical properties over a wider range of temperatures therefore they are better at maintaining viscosity at higher temperatures and less likely to become too viscous, or even solid, at lower temperatures.

Synthetics are also less prone to degradation therefore in theory, should increase the amount of time allowable between oil changes, but in practice oil manufacturers and mechanics still recommend changing synthetic oil at the same frequency as a mineral oil.

It is okay to switch between synthetic oil and conventional mineral oils in the same engine. They are compatible with each other but if in any doubt always check with your dealer or motor mechanic. It’s also worth paying a little more for a quality oil.

The life of your engine depends on it, it’s simply a false economy to make a cheap oil change.

photo credit: deansouglass