0W-40 vs. 5W-40

What's the Difference?

0W-40 and 5W-40 are both types of motor oil commonly used in vehicles. The main difference between the two lies in their viscosity ratings. The "0W" in 0W-40 indicates that the oil has a lower viscosity at cold temperatures, making it more suitable for colder climates. On the other hand, the "5W" in 5W-40 suggests that the oil has a slightly higher viscosity at cold temperatures compared to 0W-40, but still performs well in colder conditions. Both oils have the same viscosity rating at operating temperatures, which is 40. Therefore, the choice between 0W-40 and 5W-40 depends on the climate and temperature conditions in which the vehicle will be driven.


Temperature RangeWideWide
Recommended forExtreme cold conditionsCold to moderate conditions
Engine TypeGasoline and dieselGasoline and diesel
API CertificationSNSN
ACEA SpecificationA3/B4A3/B4
Oil Change IntervalLongerLonger

Further Detail


When it comes to choosing the right motor oil for your vehicle, there are several factors to consider. One of the most important decisions is selecting the appropriate viscosity grade. In this article, we will compare the attributes of two popular motor oil grades: 0W-40 and 5W-40. While both oils have their advantages, understanding their differences can help you make an informed decision for your vehicle's specific needs.


Viscosity is a measure of a fluid's resistance to flow. It plays a crucial role in protecting your engine by ensuring proper lubrication under various operating conditions. The first number in the oil grade represents its viscosity at low temperatures, while the second number indicates its viscosity at high temperatures.

Starting with 0W-40, the "0W" indicates that this oil has excellent cold-start performance. It flows smoothly even in extremely low temperatures, providing quick lubrication to critical engine components. This attribute is particularly beneficial in colder climates or during winter months when engines tend to experience more strain during start-up.

On the other hand, 5W-40 has a slightly higher viscosity at low temperatures compared to 0W-40. While it may not flow as easily during cold starts, it still offers good cold-weather performance. This oil grade is suitable for regions with moderate to mild winters, where extreme cold is not a significant concern.

Temperature Range

Another important aspect to consider is the temperature range in which the motor oil can effectively operate. This factor is crucial as it determines the oil's ability to maintain its viscosity and provide adequate lubrication under different conditions.

0W-40 is designed to perform exceptionally well in both low and high-temperature environments. Its low-temperature viscosity ensures easy flow during cold starts, while its high-temperature stability prevents excessive thinning and maintains proper lubrication even under extreme heat. This makes it an ideal choice for vehicles that experience a wide range of operating temperatures.

Similarly, 5W-40 also offers a broad temperature range, although it may not perform as well as 0W-40 in extremely cold conditions. However, it still provides reliable lubrication and protection in most climates, making it suitable for vehicles operating in regions with moderate temperature variations.

Fuel Economy

Fuel economy is a significant concern for many vehicle owners, as it directly impacts their overall operating costs. The choice of motor oil can influence the efficiency of the engine and, consequently, the fuel consumption.

0W-40 motor oil is formulated to minimize internal friction within the engine, reducing energy losses and improving fuel efficiency. Its low viscosity at low temperatures allows for easier flow, reducing the initial resistance and improving overall engine performance. This attribute makes it an excellent choice for those seeking better fuel economy.

On the other hand, 5W-40, while still providing good lubrication, may not offer the same level of fuel economy benefits as 0W-40. Its slightly higher viscosity can result in slightly higher internal friction, leading to slightly reduced fuel efficiency. However, the difference in fuel consumption between the two grades is generally minimal and may not be noticeable in everyday driving conditions.

Engine Protection

Engine protection is a primary function of motor oil, and both 0W-40 and 5W-40 excel in this aspect. These oil grades are designed to provide excellent lubrication and prevent wear and tear on critical engine components.

0W-40 offers exceptional protection, especially during cold starts when engines are most vulnerable to damage. Its low-temperature viscosity ensures that engine parts receive immediate lubrication, reducing friction and wear. Additionally, its high-temperature stability prevents oil breakdown and maintains a protective film on engine surfaces, even under extreme operating conditions.

Similarly, 5W-40 provides reliable engine protection, although it may not offer the same level of cold-start performance as 0W-40. Nevertheless, it still maintains proper lubrication and safeguards against wear and tear, ensuring the longevity and optimal performance of the engine.

Compatibility and Applications

Both 0W-40 and 5W-40 motor oils are compatible with a wide range of gasoline and diesel engines. They meet the industry standards and specifications required for modern vehicles, making them suitable for most applications.

0W-40 is often recommended for high-performance engines, including turbocharged or supercharged engines, as well as vehicles that undergo severe driving conditions or extended drain intervals. Its ability to provide excellent protection and performance under extreme conditions makes it a popular choice among enthusiasts and those seeking top-tier performance.

On the other hand, 5W-40 is a versatile oil grade that can be used in various vehicles, including passenger cars, SUVs, and light trucks. It is suitable for both gasoline and diesel engines, making it a practical choice for everyday driving and general-purpose applications.


Choosing the right motor oil for your vehicle is crucial for its performance, longevity, and overall protection. While both 0W-40 and 5W-40 offer excellent attributes, they have slight differences that can influence their suitability for specific conditions and applications.

If you live in a region with extremely cold temperatures or want the best cold-start performance, 0W-40 is an excellent choice. Its low-temperature viscosity ensures easy flow and immediate lubrication, providing optimal protection during start-up. Additionally, if you have a high-performance engine or require extended drain intervals, 0W-40's superior performance under extreme conditions makes it a preferred option.

On the other hand, if you live in a moderate climate or do not experience extremely cold temperatures, 5W-40 is a reliable and versatile choice. It offers good cold-weather performance while still providing excellent engine protection and lubrication under normal operating conditions. Its compatibility with various vehicles and fuel types makes it a practical option for everyday driving.

Ultimately, the choice between 0W-40 and 5W-40 depends on your specific needs, climate, and vehicle requirements. Consulting your vehicle's owner's manual and considering the manufacturer's recommendations can help you make an informed decision and ensure optimal engine performance and longevity.

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