Trust the team at mytyres.co.uk to find your perfect motor oil. From Castrol to Mobil, we offer a large selection of performance engine oil. Use our products to extend the service life of your vehicle. You can search or site for free or contact us for questions about our engine oil products and fluids. We are happy to also help you by phone. View the detailed engine oil product description for these top-selling Castrol and Mobil motor oils to learn more. You can also refer to the handbook of your vehicle to find out which product to use. Each car manufacturer will make a recommendation for the right synthetic engine oil to protect all of your engine parts. For more help, you can also use our handy search feature or view the product reviews on our site. Free delivery is available on all qualifying orders – including synthetic performance oil fluids. We strive to bring you the best engine oil products!
Motor oil designations
One question is unavoidable when buying engine oil: All those names and numbers - Castrol, Mobil, 5W-40, 0W-40 - what do they mean? The brand name can have an impact, but what is most important when looking for engine oil is the oil viscosity. Most of the time, it's enough to take a look at the manufacturer's recommendations to find the SAE viscosity class as well as any API classification and ACEA specification needed for a car. These should generally be respected because not doing so can void the warranty of a car.
Viscosity refers to the internal friction of a fluid. SAE stands for Society of Automotive Engineers and signifies the motor oil grade, while differentiating between summer and winter oils (also known as single-grade oils). Most drivers prefer multi-grade oils, which are suitable for all seasons - for example, a SAE 10W-40 oil. The number in front of the “W” (which is short for 'winter', meaning that the oil can be used in winter) stands for the motor oil's minimum viscosity. The number following the “W” indicates the maximum temperature at which the oil can be pumped.