Engine oil is the lifeblood of your vehicle. Not only does it lubricate internal parts, it also reduces friction, prevents overheating and cleans away debris generated by daily use. Proper oil maintenance means greater efficiency, fewer costly repairs and a longer life for your car.
Drivers often underestimate its importance, but just one oversight is enough to cause serious damage such as premature engine wear, leaks or even the need for a complete overhaul.
That's why, in this article, you'll discover the seven most common mistakes related to motor oil use and, most importantly, how to avoid them to keep your car in top condition
Mistake 1: Using the wrong type of oil
Consequences of choosing the wrong viscosity
Viscosity is a measure of how fluid the oil is. If you use oil that is too thick in an engine designed for a lighter fluid, it will not circulate well when cold, causing wear. Conversely, if you use oil that is too thin, the engine may not be protected at high temperatures.
The wrong oil choice also affects fuel consumption and overall performance.
Differences between mineral, synthetic and semi-synthetic oils
There are three types of oil, and understanding why we need engine oil in our vehicle is a fundamental part of making the right choice.
Some basic differences:
Types of oils
Basic difference between the three types of oil:
Cheaper, but lower performance.
Offers better protection, especially in extreme temperatures.
A compromise between quality and price.
Learn more about the different types of oil here. Choosing the right type of oil will depend on your vehicle, weather conditions and driving style.
Mistake 2: Not changing the oil on time
What happens when the recommended intervals are exceeded:
- Increased internal wear
- Possible blockages in the lubrication ducts
- Risk of overheating
Signs that your oil needs to be replaced
Some signs that indicate it is time to change the oil:
- Very dark colour or visible particles
- Burning smell
- Warning light on the dashboard
For passenger cars, most manufacturers recommend changing the oil between 15,000 and 20,000 kilometers or once a year, depending on the type of oil and conditions of use.
Mistake 3: Not checking the oil level regularly
How to measure the oil level correctly
- Park the car on a flat surface.
- Wait a few minutes after turning off the engine.
- Remove the dipstick, clean it and reinsert it.
- Check that the level is between the minimum and maximum marks.
Risks of driving with low or excessive oil
- Low level: can cause excessive friction and serious damage.
- High level: causes foaming and loss of adequate lubrication.
Mistake 4: Mixing different types of oils
What happens when oils of different brands or viscosities are combined
Although it is feasible to do so in an emergency due to low levels, mixing oils is not recommended. Different additives and viscosities can alter the chemical properties, reducing engine protection.
Mistake 5: Using unnecessary or low-quality additive
Do additives really help the engine?
In most cases, modern oils already contain the additives needed to protect your engine. These can be useful in very old engines or those with high mileage. However, they are unnecessary if your engine is modern and you use a good synthetic oil.
Some additives can even damage engine seals and components.
Mistake 6: Do not change the oil filter along with the oil
What is the function of the filter in the engine? Its job is to retain impurities, metal residues and particles that circulate with the oil.
Some of the damage that could be caused by a dirty or clogged filter includes reduced oil flow, contamination of the lubrication system and even the risk of severe engine damage. For this reason, you should change the filter every time you change the oil.
Mistake 7: Ignoring the manufacturer's recommendations
The manufacturer knows the engine design and its requirements better than anyone else. Ignoring their recommendations risks reducing the car's service life.
Examples of the most common specifications
- SAE 5W-30 (very common in temperate climates)
- SAE 10W-40 used in older engines)
- ACEA and API standards that certify oil quality
Always check your manual before choosing oil.
Differences in oil use depending on vehicle type
Although the errors described apply to all internal combustion engines, not all vehicles use the same oil or have the same change intervals. Each type of engine is designed with specific requirements that must be respected. Below is a comparison of motor oil use by vehicle type:
Vehicle type | Recommended oil type | Change interval (approx.) | Important features |
| Passenger cars | Mineral, semi-synthetic or synthetic oils (depending on manufacturer). Example: SAE 5W-30 / 10W-40 | Every 15,000–20,000 km or 1 year (depending on oil and usage) | Prioritises fuel efficiency, low emissions and cold start protection. |
| Motorcycles | Special motorcycle oils that comply with JASO MA or MB standards (protect the engine and wet clutch) | Every 3,000–6,000 km (more frequently than in cars) | Using passenger car oil in a motorcycle can damage the clutch and gearbox. |
| Heavy vehicle fleets | High-strength oils (SAE 15W-40 / 10W-40), API CI-4, CK-4 or ACEA E7/E9 approved | Every 30,000–50,000 km (depending on load and conditions) | They must withstand high temperatures, long journeys and heavy loads. |
| Agricultural and industrial machinery | Multifunctional oils (UTTO or STOU) that lubricate the engine, transmission and hydraulics | Every 200–400 hours of operation | The oil must be resistant to dust, moisture and extreme operating conditions. |
Basic mistakes when using oil apply to all engines, but specific specifications vary depending on the type of vehicle. Therefore, we should always consult the manufacturer's manual.
Oil is the silent protector of the engine, so avoiding mistakes such as using the wrong oil, not changing it on time, or ignoring the filter can make the difference between a long-lasting engine and a costly repair.
Remember to check the oil level regularly, follow the manufacturer's manual, change the oil and filter on time, and do not fall for myths or use unnecessary additives.
FAQs
Frequently asked questions about engine oil:
It is recommended at least once a month or before long journeys.
Yes, as long as you have the necessary tools and know how to do it.
The engine will receive contaminated oil, which can cause accelerated wear.
It will not necessarily be better. The important thing is to follow the manufacturer's specifications.
Yes, they generally have a longer service life and provide better protection.
Need more advice?
By choosing FUCHS TITAN oils, you are not only protecting your engine, but also investing in proven quality, proven performance and long-term reliability.
If you would like further advice or information on how to choose the best lubricants for your vehicle, please contact our team of experts using the following enquiry form.
You can also get an overview of our wide range of automotive lubricants for passenger cars and commercial vehicles in our > Product Finder.
Would you like to search for yourself? With the FUCHS > Oil Selector, you will be guided step by step to the optimum lubricant for your vehicle.
