10w50 and 10w40 oils have different viscosities at high temperatures. These different viscosities affect their performance and suitability for different engines.
So, can I use 10w50 instead of 10w40? If your vehicle’s manufacturer recommends using 10w50 oil instead of 10w40, you can use it. If your engine requires 10w40 oil, it may not benefit from the increased protection of 10w50 oil. And it may even cause some problems in the long run. On the other hand, if your engine can tolerate 10w50 oil, you may use it as an alternative to 10w40 oil. Especially if you drive in hot climates or under severe conditions.
In this article, we will be comparing two popular oil grades: 10W50 and 10W40. Both are popular options for high-performance engines, but they offer different benefits and are better suited to different types of vehicles.
Can I Use 10w50 instead of 10w40? Know About The Oils First!
The straight answer to the question is yes. You can use 10w50 instead of 10w40. But it’s important to consider your engine type and the manufacturer’s recommendations. 10w50 is equivalent to 10w40 in viscosity at low temperatures. But they differ in high-temperature viscosity (50 and 40, respectively).
What is 10W50 oil?
10W50 oil is a high-viscosity oil that is commonly used in high-performance engines and hot climates. This oil has a high viscosity index, which means that it retains its viscosity even in high temperatures.
The high viscosity of 10W50 oil helps to protect the engine from wear and tear, particularly in high-performance engines where the engine runs at higher temperatures. This type of oil is also ideal for use in older vehicles that are more prone to engine wear and tear.
The benefits of using 10W50 oil include improved engine protection, better performance in hot climates, and increased reliability in older vehicles. However, it is important to note that using this oil in a vehicle that is not designed for it can result in reduced fuel efficiency and increased wear on the engine.
What is 10W40 oil?
10W40 oil is a lower-viscosity oil that is commonly used in everyday vehicles and cold climates. This oil has a lower viscosity index than 10W50 oil, which means that it is more fluid in cold temperatures.
This makes it ideal for use in vehicles that are driven in cold climates, as the oil will flow more easily, providing better engine protection in these conditions.
The benefits of using 10W40 oil include improved fuel efficiency, better engine protection in cold climates, and reduced wear on the engine. However, it is important to note that using this oil in a high-performance engine or in hot climates can result in reduced engine protection and increased wear on the engine.
When to use 10W50 oil?
10W50 oil is best suited to high-performance engines, hot climates, and older vehicles. It offers improved engine protection and performance in these conditions, but it may result in reduced fuel efficiency in vehicles that are not designed for its use.
When to use 10W40 oil?
10W40 oil is best suited to everyday vehicles, cold climates, and newer vehicles. It offers improved fuel efficiency and engine protection in these conditions, but it may not provide the same level of performance and protection as 10W50 oil in high-performance engines and hot climates.
10w40 Vs 10w50, Which Is Better?
The answer to the question is not so easy to describe in one word. Before getting into further discussion, let’s see the difference between 10w40 and 10w50.
| Features | 10W50 Oil | 10W40 Oil | Reason |
|---|---|---|---|
| Viscosity | Higher | Lower | The number before the “W” in the viscosity rating (10W) indicates the oil’s cold-temperature viscosity, and the second number (50 or 40) represents the oil’s hot-temperature viscosity. A higher hot-temperature viscosity means the oil is thicker and can provide better protection in high-temperature environments. |
| Temperature Range | Better for high temperatures | Suitable for moderate temperatures | 10W50 oil is more suitable for engines that run at high temperatures or under heavy loads, whereas 10W40 oil is better for moderate temperatures and light to moderate loads. |
| Fuel Economy | Lower | Higher | Because 10W50 oil is thicker, it can create more drag on engine components and reduce fuel efficiency, whereas 10W40 oil flows more easily and can help improve fuel economy. |
| Cold-Weather Performance | May cause issues in cold weather | Better for cold weather | 10W50 oil may not flow as easily in cold temperatures, which can cause issues during cold starts, whereas 10W40 oil has better cold-weather performance and can flow more easily in colder temperatures. |
| Engine Wear | Provides better wear protection | Provides good wear protection | The thicker viscosity of 10W50 oil can provide better wear protection in high-stress or high-load engine environments, whereas 10W40 oil can still provide good wear protection but may not be as effective in high-stress situations. |
| Oil Change Interval | May require more frequent changes | May allow for longer change intervals | Because 10W50 oil can break down more quickly in high-temperature environments, it may require more frequent oil changes, whereas 10W40 oil can typically last longer and may allow for longer change intervals. |
The primary difference between 10W50 and 10W40 oil is their viscosity. 10W50 oil is higher in viscosity and is better suited to high-performance engines and hot climates, while 10W40 oil is lower in viscosity and is better suited to everyday vehicles and cold climates.
In terms of engine protection, 10W50 oil offers better protection in high-performance engines and hot climates due to its higher viscosity. On the other hand, 10W40 oil provides better engine protection in cold climates due to its lower viscosity and improved flow.
In terms of performance, 10W50 oil can help improve the performance of high-performance engines by providing better protection and reducing engine wear and tear.
However, using 10W50 oil in a vehicle that is not designed for it can result in reduced fuel efficiency. 10W40 oil, on the other hand, can improve fuel efficiency in everyday vehicles but may not provide the same level of protection and performance as 10W50 oil in high-performance engines.
Also Read: using 15w40 instead of 10w30 oil
For example, see here Viscosity and Performance Variations Between Motul 4T 10W50 and Motul 4T 10W40
FAQ’s
Check out for more queries related to 10w40 vs 10w50.
Q: Can I use 10W50 on every motorcycle?
Yes, but the answer depends on your motorcycle’s specifications and the manufacturer’s recommendations. Many motorcycles can use 10W50 oil, but some may require a specific viscosity or type of oil. It is best to consult your motorcycle owner’s manual or a trusted mechanic to determine if 10W50 oil is appropriate for your specific motorcycle.
Q: Can you mix 10W40 with 10w50?
It is generally not recommended to mix different viscosity oils like 10W40 and 10W50. When you mix oils with different viscosities, it can result in unpredictable performance and can compromise the oil’s ability to protect the engine properly.
It is best to use one type of oil that matches the manufacturer’s recommended viscosity range for your vehicle. If you want to switch from 10W40 to 10W50 or vice versa, it is recommended to perform an oil change and use only the new oil.
Q: What is the difference between a Motul 300v 10W40 and 10W50 engine oil?
The primary difference between Motul 300v 10W40 and 10W50 engine oils is their viscosity rating. Motul 300v 10W40 has a viscosity rating of 10 when cold and 40 when hot, while the 10W50 has a viscosity rating of 10 when cold and 50 when hot. The 10W50 oil is thicker and provides better protection against high engine temperatures and stress.
The difference in viscosity rating also means that 10W50 oil may be better suited for high-performance engines that generate more heat and require more protection. However, it is important to note that the specific performance benefits of each oil may vary depending on the type of engine, driving conditions, and other factors.
Final Takeaways
Finally, the choice between 10W50 and 10W40 oil depends on the type of vehicle, the driving conditions, and the performance needs of the engine. 10W50 oil is best suited to high-performance engines, hot climates, and older vehicles, while 10W40 oil is best suited to everyday vehicles, cold climates, and newer vehicles.
It is important to choose the right oil for your vehicle to ensure optimal performance and engine protection. It is recommended to consult with a professional or the vehicle’s owner’s manual for the best recommendation for your specific needs.
