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Tyres  /  Tyre NewsHelp and Advice  / What Oil Does My Car Need?

What Oil Does My Car Need?

What Oil Does My Car Need?

Having the correct type of oil in your engine is particularly important for the maintenance of your car.

Whilst electric vehicles do not need oil for the car to run smoothly, all diesel/petrol cars need lubricant for their engine.

Put simply, engine oil helps your car engine run smoothly and efficiently, meaning oil for your engine is a crucial component for smoother driving. 

Car engine - What Oil Does My Car Need?

What oil you need and how much for your engine varies between different engine types – a four-cylinder engine will take around 3.5 - 4.5 litres of oil, six-cylinder requires around 4.5 - 5.5 litres, and an eight-cylinder engine will need 5.5 - 7.5 litres of engine oil.

There are numerous types of oils available on the market, making the process of choosing the right oil for your specific car engine overwhelming.

When searching for engine oil for your vehicle, it is also crucial you understand the details behind engine oils and what type of oil your car will need – the small and valuable information on oil for your engine will be covered here today.

Understanding Viscosity

Viscosity is the measurement of a specific liquid’s flow resistance under different temperatures.

So, if a liquid in general has low viscosity, it will have a thinner flow, i.e., water, milk, juice. On the other hand, if a liquid has high viscosity, it will have a thicker texture, like syrup or honey.

To put the measure of a viscosity in more simpler terms – the lower viscosity a liquid has the faster it will flow, with higher viscosity having a slower flow.

Viscosity refers to the flow of all different types of liquids, but how does this relate to engine oils?

Oil Viscosity Measurements

When you are looking for oil that your car engine requires, you will notice the labelling on the products including numbers that may not seem familiar to you. In this case, these are simply the oil’s viscosity measurements.

The most common oils you are likely to come across when shopping for your car engine consist of 5W-30, 5W-20, and 0W-20 engine oils. These oil resistances are broken down by two numbers and a “W”.

The first number of the oil viscosity numbers (before the “W”) represents the measurement of how an oil flows at cooler temperatures. These temperatures include generally cold conditions, or even when the engine first starts up for the day.

The “W” stands for “Winter”, which is why the letter is paired with the first number of the viscosity measurement. This is again to stand for cooler conditions when relating to the flow of an oil.

The latter number of the measurement is the flow of the oil in normal/warmer conditions.

As explained earlier, the lower viscosity of a liquid means the easier it will be to flow – this applied to the viscosity of an engine oil. However, higher viscosity is recommended for warmer temperatures, as the thickness of the oil will make the oil more fluid in such conditions.

For example, if an oil has 5W-20 viscosity, it will flow faster in all colder than an oil with 10W-30 viscosity.

However, an oil that has a 5W-20 viscosity will flow slower in winter conditions, but more or less flow the same in normal/warm conditions compared to a 0W-20.

This is because the “Winter” number is higher, meaning the oil liquid is slightly thicker than the 0W-20 engine oil.

What Oil Viscosity Does My Car Take?

Every car will differ in oil grading, which is down to the size of the car’s engine design and the specifications of the vehicle.

For instance, a popular car model in the UK, the Vauxhall Corsa, may recommend using 5W-30 oil dependent upon engine types, as does over vehicles such as the Ford Focus and Volkswagen Polo.

It is advised to check your vehicle handbook when figuring out what type of oil your car is suggested to take, as manufacturers will inform of what viscosity grading your oil should be.

Car Engine Oil Specifications

In Europe, there are a rating system regarding car engine oils that breaks down near enough every oil on the market’s specification.

These specification categories are outlined by the European Automobile Manufacturers Association (ACEA).

ACEA is a group that advocates for the automotive industry throughout Europe. The group’s main focuses are to find solutions for all things automotive, focusing on areas such as efficiency, safety, reliability, and environmental.

In 1998, ACEA issued new oil standards, which included a set of specifications that can be identified for car engine oil products.

ACEA categorise different oil types for different engine and performance requirements of certain engines, which are:

These ACEA oil categories are broken down further into lettered and numbered specifications.

These numbers are shared between A, B, and C categories, such as A3, B5, or C2.

To check what each specification stands for, ACEA offer a comprehensive breakdown on each specification category to look out for when purchasing a specific oil type for your car engine.

Engine Oil FAQs

Can I Drive with Low Engine Oil?

It is not recommended to drive a vehicle with low engine oil. Lack of engine oil can be detrimental to your vehicle, as low lubricated engines causes increased friction between the metal mechanisms of the engine. This can lead to a higher chance of your car engine overheating, heightening the risk of engine failure.

Is 5W-20 Oil Better for Mileage Than 5W-30?

The viscosity of an engine oil measures the oil’s performance for specific weather conditions. In this case, 5W-30 oil will offer better mileage in hotter temperatures, as the oil type’s liquid is slightly thicker than the 5W-20. For colder conditions, both types of liquid will perform the same since both measurements are “5W”.

What Happens if I Use the Wrong Engine Oil?

Using the wrong oil may lead to damage to your car engine. If there is a wrong type of viscosity oil in your engine, the lubricant will not flow in the manner it should be, which does not lubricate your engine’s components properly. Risks of engine failure are increased as the wrong liquid type can cause more friction to the car engine’s component, leading to potential wearing and overheating.

Is Thicker Engine Oil for Older Engines?

Yes, thicker engine oil is more well equipped than a thinner viscosity oil. Older engines that have more mileage have more worn components throughout the engine, meaning a thicker and higher viscosity oil can lubricate the engine more efficiently. This leads to a better fuel consumption and prevention in oil leaks, which engines are prone to as they get older.

Does Engine Oil Deteriorate with Age?

Yes, engine oil will degrade the older the oil gets. Typically, the average unopened engine oil can last around 5 years. After the oil is past its expiration, the oil will not be as efficient as in-date oil and may damage components of your engine.

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