Semi-synthetic engine oil explained

While mineral oil is pretty much natural and are derived from the crude oil refining process. The thicker by-products are used as tar; the substances that are rich in carbon are used to make petrol and diesel. The remains are then used to make mineral oils. Keeping in mind the fact that its extraction process is extremely simple it is highly unstable and extremely prone to losing its viscosity. Further they also hold particles that make your car prone to sludge build up. But Mineral oil is extremely affordable. 

On the other end of the spectrum is synthetic oil. Highly viscous, it is a lot more versatile than mineral oil when it comes to handling changes in temperature and engine load. Usage of synthetic oil also reduces sludge formation ensuring longevity of engine life. But unfortunately, the process of making synthetic oil is long and demands a lot of research which has a direct effect on its price. 

So what then is the solution for someone who is looking to buy good engine oil at an affordable price point? Semi-synthetic oil at some level is the best of both worlds. 

Semi-synthetic oils are a mix of mineral oil and pure synthetic oils. Compared to mineral oils, these are more viscous and have a better capacity of lubricating at very high temperatures. Usually no more than 30 per cent of the mix is synthetic oil. Motul was the first manufacturer to introduce semi-synthetic oil in 1966.

The advantages of semi-synthetic engine oils are that they are cheaper than pure synthetic oils, while being better than mineral oils. These oils can be used in most road cars as they have a high viscous capacity, heat transfer capability and additives which keep the engine safer, longer. They have a longer change schedule compared to mineral oils and are better at managing sludge formation too.

Semi-synthetic oils suffer from the shortcomings of the mineral oil used to make them. They are not as good as synthetic oils, tend to have shorter change schedule and may not be able to handle extreme situations as well. Semi-synthetic engine oils are a good option for those seeking a better alternative to mineral oils but find the pure synthetic oils too expensive.