What’s The Difference Between 0w30 Vs 0w40 Engine Oil

Multigrade viscosity oils maintain thickness and thinness as they should with temperature changes. So, keeping the correct viscosity of oil in your vehicle’s engine is critical.

To do this, you need to know the main differences between different viscosity grades. In the article, we will discuss the basic differences between 0w30 vs 0w40 and answer some frequently asked questions. So stay with us to uncover some exciting facts that can help you select the appropriate oil for your engine.

0w30 Vs 0w40

0w30 & 0w40: What Do They Mean?

0w30 and 0w40 oils are often used in diesel and gasoline engines to protect the engine over a wide temperature range. They are useful for winter temperatures.

Multigrade viscosity oils contain an improved viscosity. So, they allow the oil to be liquid at low temperatures and thick at high temperatures. Multigrade viscosity contains two numbers that indicate the viscosity performance of the oil at high and low temperatures.

Difference Between 0w30 Vs 0w40:

Let’s uncover some crucial differences between 0w30 and 0w40.

Fuel Economy

As more people use car engines, the demand for different types of oil increases. People like 0w30 motor oil over 0w40 because it’s lighter and provides better fuel economy. However, it’s important to remember that 0w30 motor oil does not provide good protection against wear in the vehicle.

Temperature Range

Motor oil is an important element of a vehicle engine. This ensures that the machine is kept lubricated for smooth operation without experiencing wear from corrosion or friction or high temperatures.

Furthermore, motor oil is classified as heavy, light, or medium viscosity depending on its thickness and weight. There are several types of motor oil available for purchase, but most vehicles need 0w30 or 0w40 motor oil.

Mainly, 0w30 has a maximum kinematic centistokes average temperature of 12.5, while 0w40 has a maximum of 16.3. Thus, the minimum requirement for each is 9.3 and 12.5.


Choosing your engine oil viscosity is a concern for many drivers, and rightly so. The thickness of engine oil can determine how well it resists wear on the motor.

Also, the thickness determines how it handles in high-temperature conditions. Most cars recommend a 0w30 or 0w40 motor oil, some smaller engines require 0w20 or 5w20 to operate.

Because they contain the same grade number, 0w30 and 0w40 are great in cold weather. Nevertheless, 0w40 outperforms 0w30 in high-temperature performance, with figures slightly higher than 0w30.

Price Difference

Although the price difference between 0w30 and 0w40 is only peanuts, 0w30 costs a little more than 0w-40. However, engine oil prices vary by manufacturer.

Moreover, chemical formulas, innovative technology, and quality also greatly impact how much oil should be.


0w30 and 0w40 are used in passenger cars, vans, and light truck engines. Most automakers recommend this viscosity oil for use in their cars.

However, 0w40’s wider temperature range makes it more likely to be used in heavy-duty applications and motorcycles. 0w30 and 0w40 both are winter-grade oils which means they ensure high protection for driving in cold regions.

0w30 vs 0w40 Mercedes:

Oils whose weight, or viscosity, is suitable for low temperatures have a “W” after the number. Some oils are good for both hot and cold weather and are referred to as multi-viscosity, all-temperature oils.

And these are the oils listed for use in most Mercedes vehicles. 0w30 and 0w40 weight multi-viscosity oil is recommended for most models.

0w30 vs 0w40 BMW

All BMW manufacturers recommend 5w30 motor oil for BMW engines. No mention of 0w30 motor oil and 0w40 motor oil. But, you can use 0w30 motor oil in times or places if the weather is freezing.

In contrast, 0w40 motor oil is best for extreme weather as it is perfect for start-ups. But given that, you should still refer to your vehicle manufacturer’s recommendations.

0w30 vs 5w40

The 0w30 motor oil contains low viscosity and it can be a replacement for 10w30 or 5w30 motor oil.

5w40 motor oil refers to engine weight and viscosity. The notable characteristics of a 0w30 motor oil are heat and oxidation stability, balanced composition, and low-temperature requirements.

These motor oil properties make 0w30 motor oil capable of providing big improvements in your fuel economy. On the other hand, 5w40 motor oil can develop fuel economy.

Subsequently, 5w40 motor oil comes with a high viscosity, which means it’s not suitable for all temperatures. 5w40 motor oil contains winter viscosity grade five. That means it is less dangerous if it’s at a lower temperature.

0w20 vs 0w30 vs 0w40

In low temperatures, 0w20 and 0w40 motor oil provides the same viscosity rating of zero. In addition, 0w20 motor oil and 0w40 motor oil have the same viscosity rating of zero in low temperatures.

Usually, 0w20 motor oil has a lower viscosity than 0w30, thus, it is slightly thicker than the former. Moreover, 0w20 motor oil has a higher temperature than 0w40 and 0w30.

In particular, 0w20 motor oil is recommended for use in Honda and Camry vehicles. Furthermore, you can use it in engines which 5w20 is recommended for. All of them provided better fuel economy. Most of the engines choose 0w20 for their engine, many use 0w20 and some are 0w40 motor oil.

If you want to compare the price, 0w20 is more expensive than 0w30 and 0w40. Though 0w20 is a little more expensive, you must choose the right engine oil. Ergo, before choosing the right oil for your engine you should check your owner’s manual.

Read: Can I use 0W20 instead of 5W20?

FAQ (Frequently Asked Questions):

Q. Can you mix 0w30 and 0w40?

You can mix any motor oil with other motor oils regardless of viscosity (0W30, 0w40, etc.). The only thing you should try not to do is mix old-school dino oil with synthetic oil. A synthetic should be used if the car is synthetic. If there is a dyno, use the dyno.

Well, you can mix dyno and synthetic to some extent, if it is urgent but you should change it as soon as possible.

Q. What is 0W40 oil used for?

Automakers recommended using 0w40 oil for most European vehicles, including Mercedes-Benz, Volkswagen, and Porsche. Viscosity is gaining popularity with American automakers for high-performance engines in both pickup trucks and cars.

Q. Is 0W40 good for hot weather?

Accordingly, 0w40 is a thinner oil and ideal for extreme temperatures in summer and winter. So, you can use this 0w40 motor oil when you are in hot weather.

Q. What is 0w30 oil used for?

0w30 motor oil can help enhance the engine performance and fuel economy compared to higher viscosity oils.

Adequately, 0W-30 oil is significantly suitable for heavy-duty, high-performance diesel engines, light trucks, and passenger cars. Diesel engines face the problem of engine deposits and buildup, and 0W-30 oil can remove this problem with protection.

Final Word

0w30 vs 0w40, though there are many differences there are common things. The common thing is that they can perform very well at low temperatures. Additionally, they are also suitable for high-temperature.

But from 0w40 you can get a slight advantage over 0w30 at very hot temperatures. Overall, we hope this article enlightens you with all the information you need.

Read Also: 0w30 Vs 5w30


Emon is Lubricants specialist who studied on Petroleum Engineering in UAE. He have more than 10 years experience on different kinds of lubrication including automobile troubleshooting.