Which Engine Oil Is Suitable for My Car?

Before exploring the details of engine oil, it’s a good idea to check your vehicle owner’s manual. Inside, you’ll find the manufacturer’s recommended viscosity grade, approvals, and specifications designed specifically for your engine.

Viscosity refers to how easily engine oil flows while protecting internal components. A higher viscosity means the oil is thicker and flows more slowly, while a lower viscosity allows it to circulate more freely.

Oil grades are displayed as a combination of numbers and letters, such as 5W-40. The “W” stands for winter. The number before the “W” indicates how the oil performs in colder temperatures — lower numbers mean the oil remains thinner in cold weather, helping with easier starts. The number after the hyphen reflects how the oil performs at high operating temperatures (around 100°C).

Using oil that is too thick can reduce engine efficiency, as more energy is required to circulate it through vital components. Many modern engines are designed to work best with lower-viscosity oils that support improved performance and efficiency.

Fully synthetic oils are entirely man-made formulations without mineral oil blends. They are engineered to resist heat and oxidation, maintain stability for longer periods, and generally provide superior engine protection and performance.

Semi-synthetic oils combine mineral and synthetic bases, offering a balance between cost and performance. While more affordable, they typically do not match the durability and protection levels of fully synthetic options.

Switching from semi-synthetic to synthetic oil usually does not cause issues, provided the oil meets your vehicle manufacturer’s recommended specifications. The most important factor is selecting an oil grade and type approved for your engine. Always refer to your handbook or a reliable oil finder tool to ensure compatibility.

Synthetic oils offer several benefits, including improved fuel efficiency and easier cold starts due to better flow at low temperatures. Their refined formulation also reduces impurities, supporting cleaner engine operation and lower emissions.

Mobil 1 oils, used by ESP Servicing, feature advanced additive technology designed to minimise wear, control oil breakdown, and help prevent sludge and deposit build-up — all contributing to longer engine life.

It is possible to alternate between synthetic and semi-synthetic oils. However, if you move from a fully synthetic product to a semi-synthetic blend, you may notice a reduction in performance benefits. Whatever you choose, ensure the oil matches the manufacturer’s recommended grade and specification, and select the highest-quality option available for optimal engine protection.