Oils > Engine oil

everything you need to know about car engine oils

Engine oil is an essential component in any vehicle's engine, ensuring its smooth operation and longevity. There are a wide range of engine oils on the market and it can often be difficult to decide which oil is right for your car. In this article, we'll look at why engine oil is important, what its main types are, and how to choose the right oil.

Why is engine oil important?

Engine oil performs several important functions:

1. lubrication : reduces friction between moving parts of the engine, which in turn extends the life of the engine.

2. Cooling : helps dissipate heat generated in the engine at high temperatures.

3. cleaning : removes dirt and soot that form during engine operation.

4. Corrosion prevention : protects engine parts from rust and oxidation.

Regular oil changes ensure that the engine oil can perform these functions to the maximum.

 

main types of engine oils

Motor oils can be divided into three main categories:

1. Mineral oils : made from crude oil and are suitable for older or lower-duty engines. They are usually cheaper but require more frequent changes.

2. Semi-synthetic oils : contain a blend of mineral oils and synthetic oils. They offer better protection and longer service life than mineral oils.

3. Synthetic oils : made from chemically modified oils, offering the highest quality and protection. Suitable for modern engines and extreme conditions.

viscosity and its meaning

The viscosity of motor oils is determined based on SAE (Society of Automotive Engineers) standards. For example, the meaning of the oil type "5w-30":

• "5w" : low temperature viscosity of the oil ("w" stands for winter). The lower the number, the better the oil flows in the cold.

• "30" : viscosity at higher temperatures. A higher number means a thicker oil.

Following the engine manufacturer's specifications is critical in selecting the correct viscosity oil.

 

How to choose the right engine oil?

1. Consult your owner's manual : the car manufacturer provides clear instructions on the correct oil type and viscosity.

2. Climatic conditions : in colder regions, oils with lower winter viscosity are suitable, while in warm conditions, oils with higher viscosity should be preferred.

3. Driving style : if you use your car for intensive driving (e.g. a sports car), choose a higher quality synthetic oil.

4. extended maintenance intervals : if you change your oil less often, opt for synthetic oil.
    

Frequently asked questions

How often should engine oil be changed?
It is usually recommended to change the oil every 10,000-15,000 kilometers or according to the manufacturer's recommendations.

Can different oils be mixed?
Although mixing may be technically possible, it is not recommended as different additives may react unpredictably.

What happens if you use the wrong oil?
Using the wrong oil can reduce engine efficiency, increase wear and even damage the engine.

 

Choosing engine oil for the most common car brands

Every car manufacturer tests their engines with specific oils and issues the corresponding approvals (standards). This is even more important than the brand name.

Volkswagen Group (VW, Audi, Škoda, Seat)

This group uses very specific standards. Common models such as the Volkswagen Passat , Golf , Skoda Octavia and Audi A4 almost exclusively require oils that meet VW standards.

• VW 504.00 / 507.00: This is the most common long-life maintenance standard for diesel and gasoline engines. It is usually 5w-30 in viscosity.

• VW 508.00 / 509.00: Newer and more economical engines (e.g. 1.5 TSi or the latest 2.0 TDI) use the ultra-fluid 0W-20 oil. Its use in older engines is prohibited because it is too liquid.

BMW and Mini

BMW 3 Series , 5 Series and X5 owners should look out for the "longlife" signs:

• bmw longlife-01 (ll-01): older gasoline engines.

• BMW Longlife-04 (LL-04): The standard choice for modern diesel engines (with diesel particulate filter or DPF) and petrol engines. It is a "low SAPS" oil, meaning low sulphated ash, phosphorus and sulphur, protecting the exhaust system.

Toyota and Japanese manufacturers

Toyota Corolla , RAV4 and Avensis are known for their reliability, but the new hybrid models are very demanding on oil.

• Toyota recommends 0W-16 or 0W-20 oils for many new models. Japanese engineers emphasize fuel economy and quick lubrication during cold starts.

• Older models usually use an API (American Petroleum Institute) standard, such as API SN or SP.

ford

Ford Focus , Fiesta and Mondeo often use "Ecoboost" engines.

• These engines require oils that meet the WSS-M2C948-B specification (usually 5W-20). This oil is specifically designed to keep timing belts (which are oiled in an oil bath on some models) from breaking down.

best-known oil brands: who to trust?

There are dozens of manufacturers on the market, but top-notch quality is offered by brands that work closely with car manufacturers:

1. Castrol: closely associated with the Volkswagen Group and Ford. Their Edge series is known for its strong oil film.

2. Mobil 1: Works with Porsche and Mercedes-Benz to offer top-of-the-line fully synthetic oils.

3. Shell: uses a unique base oil technology synthesized from natural gas ( pureplus ) that keeps the engine exceptionally clean.

4. Liqui Moly: A German brand known for its wide range of products and specific additives.

5. Valvoline: one of the world's oldest oil manufacturers, whose MaxLife series is aimed specifically at cars with higher mileage, helping to restore seals.

6. Total / Elf: French manufacturer, the primary partner for Peugeot, Citroën and Renault models.

Engine oil additives: whether and why?

In addition to the base oil, every high-quality oil already contains components added by the manufacturer (detergents, anti-wear agents). However, there are oil additives sold separately, which are divided into three groups:

• Cleaning additives (engine flush): added to the old oil just before an oil change. They dissolve deposits and dirt so that the new oil can start working in a clean engine.

• Anti-wear additives: technologies that use ceramic particles or molybdenum to create an additional sliding layer on metal surfaces. This is especially beneficial for older engines or vehicles operating in harsh conditions.

• Leak-stopping additives: contain chemicals that soften old and hardened rubber seals, stopping minor oil leaks.

In summary: 5 golden rules for changing oil

1. Follow the manufacturer's standard, not just the viscosity: if the car requires VW 507.00, then a regular 5w-30 oil without this marking may not be enough.

2. Shorten your oil changes: Although manufacturers promise 30,000 km oil changes, experts recommend changing the oil every 10,000 – 15,000 km or once a year.

3. Always change the filter as well: new oil in an old and black filter quickly loses its properties.

4. Check the level regularly: even the best oil will not protect the engine if there is too little of it.

5. Do not mix different oils: in an emergency, you can add another oil, but a complete oil change should be performed as soon as possible.

Choosing the right engine oil is the best investment in the longevity of your car. It keeps fuel consumption under control, emissions clean and provides peace of mind with every start.

Summary

The choice of engine oil and regular maintenance are important to ensure long-term and trouble-free operation of your vehicle's engine. Always follow the manufacturer's recommendations and choose the oil according to your car's needs and driving conditions. An investment in high-quality engine oil will definitely pay off.