But what is the difference and what does it matter?
Oil is basically the most important thing in your car – it’s easy to maintain and keeping on top of it keeps your vehicle running well avoiding damage and subsequent costly repairs.
Regular checks and oil maintenance can also help to extend the life of the vehicle and engine and help to hold its value when you come to change the car.
If your car is under warranty then not using the recommended oil can invalidate that warranty - that’s how important it is
Interestingly enough all the different engine oils are developed from the same crude mineral oil that comes out of the ground.
From there they are refined; synthetic bases and additives are added and give correct viscosities and synthetic blends. They become either semi synthetic or fully synthetic and meet the requirements set by different car manufacturers.
Synthetic Vs semi synthetic
Most car owners need a fully synthetic engine oil. It tends to have longer life and is able to cope with higher temperatures and more extreme pressures this is why they tend to be used by manufacturers of modern cars as it has extended their service intervals by significant margins.
Semi synthetic engine oil is a blend and tends to have most of the benefits of synthetic engine oil, but at a lower cost and does not last as long. These are the oils typically used in older every day vehicles.
Oil is either single-viscosity or multi-viscosity and typically most vehicles are designed to run on multi-viscosity oil.
This is what the numbers and w’s are all about - the lower the number, the thinner the oil and more easily it flows.
The number before the 'w' refers to how it performs at cold temperatures and the number after is its performance at high temperatures.