5w40 Vs 10w30: Comparison, guide and review

When it comes to engine oil, there are a lot of different options on the market. It can be difficult to understand which motor oil is right for your car.

You might be wondering what the best engine oil is for your car. Well, there are a lot of factors that you should take into account while choosing the best engine oil for your car.

5w40 Vs 10w30

The 5w40 and 10w30 are two of the most popular engine oils which are suitable for a wide range of automobiles, including cars, minivans, trucks, and other automobiles.

So, we have compared the 5w40 Vs 10w30 to help you make an informed decision about which type of oil is better for your car.

What is 5w40?

5w40 is a type of motor or engine oil that is commonly used in a wide range of automobiles. It is made from a mix of synthetic and conventional oils, and it is designed to provide better protection for your engine than other types of motor oil. 5w40 is also known for providing better fuel economy than other types of motor oil.

If you’re looking for an oil that can withstand a cold climate and protect your engine during extreme conditions, then 5w40 is a good option. However, you need to check whether this engine oil is compatible with your vehicle or not.

5w40 is designed to be used in both new and older engines, and this oil can improve performance and extend engine life. 5w40 is also a good choice if you live in an area with cold winters, as it can help to prevent oil sludge and keep your engine running smoothly.

What is 10w30?

10w30 is a similar type of engine oil to that of 5w40 as it is also commonly used in different vehicles. Similar to 5w40, it is also made up of a mixture of different oils, including synthetic and conventional oils.

The main difference between 10w30 and other types of engine oils is the viscosity or thickness of the oil. 10w30 is typically thinner than other oils but thicker than 5w40, which means it can flow more easily and quickly through your engine.

This can help improve fuel economy and prevent engine wear. Most car manufacturers recommend using 10w30 motor oil in their vehicles.

10w30 is designed to provide excellent protection and performance in a wide range of temperatures, including hot and cold. 10w30 motor oil is highly suitable for use in high-performance engines.

5w40 Vs 10w30 Comparison

Name 5w40 Engine Oil 10w30 Engine Oil
Lower Viscosity 5 10
Higher Viscosity 40 30
Viscosity Index 176 146
Sulfated Ash 1.3% 0.8%
Viscosity at 100ºC 13.7 10.7
Oil Thickness Thin Thick
Fuel Economy Good Average
Engine Wear Less Less
Suitable Weather Cold (Winter) Summer (Hot) and Winter (Cold)
Ideal Temperature -30 to 40-degree celsius -25 to 30-degree celsius
Oil Base Synthetic Synthetic
Life Expectancy 8000 Miles 5,000 Miles
Replacement Required 6 to 7 thousand miles Before 4 thousand miles
Anti-Corrosion Yes Yes
Anti-foam Yes Yes
Anti-Wear Yes Yes
Vehicle Compatibility Modern Vehicles, Passenger Cars, Light Trucks, and SUVs SUV and Truck Engines
Ideal Engine Gasoline and Diesel Petrol and Diesel
Friction Least Least
Thermal Stability Good Average
Oxidation Stability Good Good

Similarities Between 5w40 Vs 10w30

Engine Wear

The first similarity between the 5w30 and 10w40 engine oil is their engine wear properties. Both the engine oil provides protection against engine wear. The 5w40 and 10w30 have a lot of additives in them, making sure to protect your engine against wear and tear.

The 5w40 and 10w30 help in reducing the piston deposits and also helps in reducing the oil consumption.

Oil Base

The 5w40 and 10w30 engine oil come with a mixture of synthetic as well as other conventional oil mixes. Both are long-lasting oils that have the base of synthetic oil.

Depending upon the brand that you choose, both oils can have different oil bases. For instance, some oils come with a fully synthetic base, while some brands offer only a semi-synthetic oil base.


Both the 5w40 and 10w30 engine oil have a lot of additives in them. Apart from the synthetic oil base, both of them have anti-oxidants, rust and corrosion inhibitors, anti-foaming agents, anti-wear agents, viscosity index improvers, and a lot more other additives.

These additives help to protect your car engine from different situations. Without the additives in the engine oil, the engine oil will perform like a conventional oil which will not only reduce the performance of your vehicle but also degrade the life of your engine over time.

Anti-Corrosion Properties

Both the 5w40 and 10w30 have a lot of anti-corrosion properties in them, which helps in protecting your engine not only against corrosion but from water and rust damage.

The 5w40 and 10w30 have corrosion inhibitors which are specially added to these oils to protect the surface of the engine components.

The corrosion inhibitors protect the component from corrosion which can be caused by mineral acids as well as organic acids, which form during oxidation.

Anti-Wear and Tear

The 5w40 and 10w30 engine oils have anti-wear properties in them, making them strong against any wear and tear which happens while you are driving the car in extreme conditions.

The anti-wear additives in both of these engine oils help against engine wear and the loss of metal surfaces.

Anti-Foaming Agents

Anti-foaming agents are used in 5w40 and 10w30 oil to prevent the formation of bubbles. Anti-foaming agents are used to preventing the formation of foam on the surface of the oil.

They are also added to both of these lubricants to help reduce wear and tear on engine parts. 5W40 and 10W30 oils have both anti-foaming agents, which means they will provide similar wear protection against metal surfaces.


There are numerous similarities between 5W40 and 10W30 lubricants, notably how much friction they produce.

These two engine oils have the lowest levels of friction. The friction may be a little less in some situations with the 5w40 engine oil than with the 10w30, but it will often be the same.

Oxidation Stability

The two oils are similar in their oxidation stability. Both the 5w40 and 10w40 have great oxidation stability. The 5w40 and 10w30 engine oils are more resistant to oxidation, which means they can be used in a wider range of conditions and situations without causing problems.

This is because it’s easier for these oils to sit on top of the metal surface and prevent rust from forming.

Difference Between 5w40 Vs 10w30

Lower Viscosity

The lower viscosity of both engine oils is different. The 5w40 engine oil has a lower viscosity grade of 5, while the 10w30 engine oil has a lower viscosity grade of 10.

Compared to 10w30, 5w40 has a lower grade of viscosity, making it easier to flow at a variety of temperatures. Furthermore, because of its low viscosity, the 5w40 is thinner than the 10w40.

Higher Viscosity

When it comes to the high viscosity of these engine oils, then the 5w40 has a higher viscosity grade of 40, while the 10w30 engine oil has a higher viscosity grade of 30.

At startup temperatures, the 10w30 will flow better in comparison to the 5w40. Moreover, the 10w30 oil will get thickened as the engine starts to drop the temperature.

Viscosity Index

The higher the viscosity index, the thicker the oil will be, and it will take longer for it to flow through a narrow opening, such as between two moving parts or around a piston or cylinder wall.

Since 5w40 has a higher viscosity index, it should be thicker, but that is not the case in this instance. Particularly when it comes to colder conditions, the 10w30 has proven to be thicker than the 5w30.

Sulfated Ash

Sulfated ash in engine oil is a mixture of metallic content that stays in the engine oil, which helps in anti-wear and tear.

The 5w40 engine oil has a sulfated ash amount of 1.3%, which is better in comparison to the 0.8% of the 10w30 engine oil. This means that your engine will have less wear over time if you use the 5w40 due to its better chemistry with other additives.

Viscosity at 100ºC

Most of the brands report the viscosity of the engine oil at two different temperatures. Either the company will report the viscosity at 100 degrees Fahrenheit or at 100 degrees Celsius.

In this case, the 5w40 and 10w30 engine oil have their viscosities reported at 100 degrees. The 5w40 engine oil will have a viscosity of 13.7, while the 10w30 will have a viscosity of 10.7.

This basically means when the temperature rises, and when it touches 100 degrees, the 10w30 will pour more easily and will have a greater flow among the components of the engine. Moreover, the friction will be very low.

The thickness of the Oil

The engine oil’s thickness tells you a lot about the oil’s quality. For instance, in low temperatures, the 5w40 motor oil is thinner than the 10w30.

The layer strength and oil pressure are better maintained by thicker oils at higher temperatures and loads. Therefore, the 10w30 is a better option than the 5w40 in this case.

Fuel Economy

The fuel economy is a big deal. If you’re looking to get the most out of your car’s fuel economy, you want to use the right oil.

While both the engine oils offer excellent fuel economy when you use them in the right type of engine and vehicle, however, the 5w40 is a slightly better option in terms of fuel economy.

Because the oil is thin, the engine performs better in different conditions. Hence you get better fuel economy with 5w40 in comparison to 10w30 motor oil.

Suitable Weather Conditions

Both the engine oils are suitable for different weather conditions, and both of them can be used in different regions, hot, cold, and other.

But to be precise, the 5w40 engine oil performs better in the winter season. On the other hand, the 10w30 engine oil performs better in the summer as well as winter seasons.

So you get freedom with the 10w30 engine oil of using it in summer as well as winter, unlike 5w40, which is restricted to be used in winter conditions.

Temperature Range

You must take into account the temperature range for both engine oils. For instance, 5w40 engine oil is recommended for use between -30 and 40 degrees Celsius.

On the other hand, the recommended temperature range for 10W30 engine oil is between -25 and 30 degrees Celsius. Since both engine oils have different operating temperatures, you can choose the engine oil you want to purchase based on your preferences.

Life Expectancy and Replacement

Life expectancy should be considered before choosing the right engine oil. D About their varying life expectancies, different brands could make certain claims about the life of engine oil.

Any brand oil that you use in your engine will typically have the same lifespan in the majority of situations. But the 5w40 and 10w30 have entirely different life spans. You can use the 5w40 oil till your automobile has covered 8000 miles, which is the range it offers in terms of mileage.

The 10w30 engine oil, on the other side, has a much lower mileage range than the 5w40 engine oil, with a range of roughly 5,000 miles. Before you go anywhere close to 8,000 miles, the 5w40 engine oil needs to be replaced.

In ideal circumstances, the 5w40 engine oil should be changed before 6,000 or 7,000 miles. On the other hand, the 10w30 needs to be changed after 4000 miles or more.

Vehicle Compatibility

As far as compatibility with various types of automobiles goes, both 5w40 and 10w30 engine oils are suitable for a wide variety of cars.

Modern cars, light trucks, SUVs, and passenger cars can all use 5w40. The 10w30, on the other hand, works with truck and SUV engines.

Compatible Engines

In addition to making sure the vehicle is compatible, you also need to examine the engine. Both gasoline and diesel engines can use the 5w40. The 10w30, on the other hand, works with both gasoline and diesel engines.

While you can also use 10w30 in gasoline engines and 5w40 in petrol engines, the manufacturer does not advise doing so.

Thermal Stability

One of the most crucial factors to take into account when selecting engine oil for your car is thermal stability. The thermal stability of the 5w40 engine oil is superior to that of the 10w30 engine oil.

When it is chilly outside, 5w40 is thermally stable, but it is not stable when it is hot outside.

Pros and Cons of 5w40 Vs 10w30

5w40 Engine Oil:

Pros Cons
Better fuel economy Not ideal to use in hot climate
Superior performance More engine wear
Least friction
Lower viscosity grade

10w30 Engine Oil:

Pros Cons
Higher viscosity grade More friction
Suitable for summer and winter
Less engine wear
Compatible with SUVs and Trucks

Which is Better: 5w40 Vs 10w30?

Both the engine oils have their own advantages and disadvantages. Depending upon the vehicle you own or the engine type you have in your car, you can choose the engine oil.

If you want better performance, fuel economy, and life expectancy, then the 5w40 is better engine oil. It has great mileage life, and you don’t need to replace the engine oil until you have driven 6 to 7 thousand miles. However, the engine wear will be more with the 5w40 engine oil.

Read: 75w85 vs 75w90

Frequently Asked Questions:

Does the 10w30 engine oil provide protection against deposits?

Yes, the 10w30 offers protection against deposits as well as wear and oxidation.

Which standards do 5w40 engine oil have?

Depending upon different brands, different standards can be followed. The 5w40 engine oil mostly follows ACEA standards.

Does 10w30 help against sludge buildups?

Yes, the 10w30 helps not only against the sludge buildups but also against the damaging deposits.


In short, both engine oils are superior in their own domains. For instance, if you want an engine oil that offers less wear and tear, has a higher viscosity grade, and is suitable for both summer as well as winter climates, then you can go with the 5w40 engine oil.

On the other hand, if you want better fuel economy, performance, and a greater replacement life, the 10w30 is a better choice for you.


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