The purpose of oil or lubricants is to reduce the friction between two metal surfaces. It does this by sticking to each surface and forming a thin film that keeps the metal components apart. The parts effectively ‘float’ on a thin film of oil or lubricant which stops metal to metal contact, reduces friction, heat and wear. The quality and performance of oil is a measure of its ability to…

Viscosity is a measure of the thickness of the oil. The viscosity of engine oil at low and high temperatures is measured on a scale determined by the Society of Automotive Engineers and given a number known as the SAE number. Therefore SAE 30 oil will be thinner than SAE 40.

Mineral oil is obtained directly from the crude-oil refining process, whereas synthetic oils are produced by synthesis process which improves its chemical structure. Synthetic oils have better performance than mineral oils at all temperatures, and are more durable. They are more expensive but are higher quality, offer higher performance and longer life.

Better oil-flow at low temperatures enabling thinner oils to be manufactured. Thinner oils are required by modern engine designers to help reduce the fuel consumption and emissions Superior lubrication between moving parts, giving better protection thereby reducing wear & tear More stable and less volatile at high temperatures, reducing oil consumption.

A semi synthetic oil is a blend of mineral and fully synthetic base oils. The performance, price, quality and durability is between that of a mineral oil and fully synthetic oil. Lower quality semi synthetic oils have very little fully synthetic content and will cause multiple problems in the engine.

A synthetic oil is produced in a more sophisticated and expensive manufacturing process. A fully synthetic oil does have many performance advantages (see above) which justify the additional cost. Fully synthetic oil allows longer service intervals, reduces oil consumption, extends engine life and contributes to improved fuel consumption – driving running costs down. It is all about quality and performance.

Synthetic oils are not fake – they are still derived from Petroleum crude. However, synthetic oils use higher base stocks than mineral oils and go through a synthesis process in which all the molecules are made into the same size for a better film strength.

Switching between synthetic and conventional oil does not cause problems. Because the oils are compatible, you can switch back and forth as often as you like.

Mixing synthetic and conventional oils will not cause any problems. The oils are compatible with each other.

The industry standard is based on the API Base Oil Classification: Group I – Conventional Paraffinic Mineral base oils Group II – Low sulphur Paraffinic and some hydro-cracked (VI below 120) mineral base oils Group III – Hydro-cracked (VI above 120) synthetic base oils Group IV – Poly-Alpha-Olefins (PAO) synthetic base oils Group V – Esters etc.

Before the 1960s, all oils were monograde. Multigrade oils were developed have a designation in the format 20w50. Mulitgrade oil was made possible by the use of polymers, that expand as they get hotter. Therefore a multigrade oil can have the viscosity of an SAE20 when it is cold and the viscosity of an SAE50 when hot. This removes the necessity to change from thin oil in the winter to…