Our cars are not invincible, and require regular maintenance to keep our cars running in good shape, with one important maintenance being the change of engine oil.

What is Engine Oil?

The components of our car’s engines are mostly made out of metal alloys, and metal alloys when they come into contact with each other, they can wear out easily, especially when the high temperatures in the engine cause the metals to expand.

That’s where engine oil, our engine’s lubricant, comes into play. Engine oil, also known as motor oil, is made up of base oils and enhanced with additives to improve the effect it has on your engine.

The purpose of engine oil is mainly as a lubricant for your engine’s moving parts, reducing the friction and wear on them, while also cleaning your engine from unwanted grime buildup and absorbing the heat produced by the engine.

Difference between different engine oils

There is a standard for grading engine oil viscosity made by the Society of Automotive 

Engineers (SAE) called SAE J300, which rates the viscosity of the engine oil at different temperatures and allows you to choose the most suitable one for your car and weather.

You might notice when shopping for engine oil, that there are ratings on the container such as 5W-40, 15W-50. The number with W stands for the low-temperature viscosity of the engine oil, also known as the winter grade, which measures how low the temperature of the engine oil can go without failing. A lower value means that the engine oil can withstand colder temperatures without failing.

The other number behind stands for the viscosity during normal operating temperatures, also known as the non-winter grade, which measures the viscosity of the engine oil flowing through an orifice. A higher number would mean a higher viscosity, which is a thicker engine oil at normal engine operating temperatures.

Which is better?

It is always best to refer back to your car’s owners manual to know the perfect engine oil grade for your vehicle, and also to know the duration or mileage that you should replace the engine oil in your car, and also the oil filter while you’re at it.

A good and new engine oil should look clear and have the viscosity it is rated for, whereas old and used engine oil will be dark, mushy and have a higher viscosity than rated for.

You can always check the condition of your engine oil by pulling out the engine oil dipstick of your car’s engine, where it will show you if there is sufficient engine oil inside, and you can also check the colour and viscosity of the engine oil on the dipstick to know if your engine oil needs a change.