20W40 Vs 10W40 Motorcycle Oil: What Are The Differences?

While keeping good engine oil in your car is important, the more important part is putting the “right type” of oil in your car’s engine. In particular, what oil viscosity you are putting in the engine is very important.

20W40 Vs 10W40

Every motorcycle owner knows about 10w40 and 20w40. Depending on the functionality and viscosity, weight, and more, you can find different types of oil. However, in this article, we will discuss the differences between 20w40 vs 10w40 motorcycle oil.

It’s because from this discussion you can understand which of them is more suitable for your motorcycle. So, don’t go anywhere, just stay with us, please.

20w40 vs 10w40 Motorcycle Oil

Before going into the detailed discussion, a brief head-to-head comparison between 20W40 and 10w40 is presented here.

Viscosity (Low Temperature) ThinnerThicker
Viscosity (High Temperature) SameSame
Oil ConsumptionLessMore
Weather SuitabilityBest for cold TemperatureBetter for hot Temperature

Now let’s go to know about these oils in detail:

Main Differences Between 20W40 Vs 10W40 Motorcycle oil:

There is a difference between 10w40 and 20w40 engine oil. However, there is not much difference at all. So let’s dive into the differences between 10w40 and 20w40 in terms of viscosity, fuel economy, and hot weather.


The “10W” in 10W40 engine oil means “winter”. It shows the high viscosity or flow of this oil in low-temperature conditions.

The lower the number you see before the “W”, the better performance you can expect in cold temperature conditions. Accordingly, 10W40 oil can provide better performance in lower temperature conditions than 20W40 oil.

See : What Is Viscosity Modifiers

Fuel Economy

Multi-grade engine oils have different viscosities at different temperatures. Motor oil must flow freely in cold weather to protect engine parts. A 10w40 oil has 10-grade oil viscosity when cold and 40-grade oil when hot.

A 20w40 engine oil can replace a 10w40 in winter or temperatures or cold weather. Nevertheless, 10w40 oil can provide better performance and lubrication over a broad temperature range than 20w40 oil.

Weather Condition

If your car is in winter, you cannot start your car easily. So if you crank your engine repeatedly, it will pressure your starter. Additionally, engine oil has a harder time traveling in the engine because this oil can be too thick to flow easily.

As a result, engines will end sooner because your engine will have too many unlubricated parts. 10w40 oil has a low w rating, which means that it will provide better and better performance in colder temperatures.

20w40 engine oil has a high w number, which means this oil won’t perform perfectly in cold temperatures. This is the difference between these 20w40 and 10w40 motorcycle oils.


Actually, you can use a 20W40 oil to replace a 10W40 oil, they perform better in warmer temperatures. Nonetheless, 10W40 oils provide better lubrication and improved performance than 20W40 motorcycle oils. Finally, it also contributes to fuel economy.

Price Difference

When you go to the shop to purchase engine oil, you get confused with the different prices and types.

In the recent era of lubricants, engine oil brands are creating specially engineered motor oils with special capabilities. Now it is like marketing trends to hold up with competitors.

At a very basic level, you’ll find three types of oil: synthetic, semi-synthetic, and conventional oil. Synthetic oil is more costly than the other two. However, prices can be measured at longer oil change intervals.

Read : How often to Change Motorcycle Oil

At the viscosity level, you won’t notice the price difference much. There is about a $1 price difference per quart between 10w-40 and 20w-40 synthetic engine oils. Regardless of the oil brand, 10w-40 may cost a little more.

Viscosity has little effect on the price of engine oil, rather the base oil and additives decide it more.

Field of Application

The manufacturer recommends 20w40 oil for 4-stroke motorcycle engines, passenger cars, high-performance vehicles, and cars operating in severe driving conditions.

High-performance cars are those utilized for heavy-duty applications such as multi-utility vehicles, 3-wheelers, commercial vehicles, tractors, etc. 20w40 oil is perfect for these vehicles.

Modern-day engines need thinner synthetic oils, so you won’t see 20w40 and 10w40 being used or suggested as much in light-duty cars.

As a primary recommendation, these thicker oils are no longer used but are used as an alternative. 10w-40 engine oil is suitable for cars that are leaking and burning oil.

Some racing motorcycles use a 10w40 oil that is specifically constructed for bikes only. Like 20w-40, 10w40 is also recommended for high-performance engines.

Can I Use 10w40 Instead of 20w40?

Actually, you can; however, always follow what your oil recommends. For example, if the recommendation for your car is only 10w40, then don’t use 20w40 and vice versa. But you have the choice to do that if you want. This is because 10w40 oil and 20w40 motor oil have a rating of 40° and 100°C.

That means both engines contain the same viscosity or thickness at 100°C. A thirty-rated oil will be thinner at the same temperature.

Accidentally Used 10w40 Replace Of 20w40: Is It Ok?

Yes, it is fine, but it would be better to use the recommended motor oil viscosity for your engine. For example, a 10w40 oil will offer better lubrication and performance over a wide range of temperatures than this 20w40 motor oil.

When Should I Use 20w40 and When 10w40?

In a 10w40 engine oil, the 10w bit means the highest viscosity the motor oil should have. The lower the W number, the better it’s for cold temperatures. 40 in 10w40 means the motor oil should be within a certain viscosity range.

In 20w40 oil, 20w bit, and W winter, that is, the motor oil should have a certain viscosity. Again, the lower the W number, the better the oil for cold temperatures. With these characteristics, you should follow the oil recommendations according to the manufacturer.

Which Is Better, 10w40 or 20w40 Oil?

If the number is small, it describes how the oil will behave at 40°C. And a 20w at 40°C is ten times thicker than your motor requires. On the other hand, 10w40 oil is much better at about six times thicker.

So the answer is that it depends on your car and some other factors. Each vehicle has its recommendations for oil and viscosity.

What Will Happen If I Use 20W40 Oil Instead of 10W40?

The odds are virtually one hundred percent you won’t know the difference. But if you live in a cold place and weather, your car may be a little harder to start. In fact, your engine may wear a little more quickly until it warms up a bit.

Accordingly, when you haven’t 10w40 on your hands, you can use 20w40. The reason is that the 20w40 oil container comes with a correct API Donut Service Section stamped.

Notably, the letters (CI, SL, CK, and SN) indicate this oil is perfect for engines called for a specific pack listed in the vehicle manual. A real reason to stick with 10w40 is that if you have a warranty, during your problem, the dealer mightn’t take care.

what will happen if i use 20w40 engine oil instead of 10w40

10w40 vs 20w40 Which Is Thicker

Beyond the 10 weight, if you live in a hot climate, you can go with a heavier base, say a 20. The lower the “W” number the better the cold temperature.

Again the higher the number, the thicker the oil: a 50 oil is thicker than a 40 oil at 100°C, etc. Your handbook will specify whether a 30, 40, or 50, etc. is required.

In a 10w-40, the 10w bit (W = winter, not weight) means the lubricant oil must have a particular maximum viscosity at low temperatures. The lower the “W” number the better the cold start performance of the oil.

A 40 in a 10w-40 means that the oil must fall within the specified viscosity range at 100°C. Additionally, it’s a fixed limit and all oils ending in 40 must acquire these limits.


A 20w-40 for example has the 20W bit and the W (WINTER). This means the oil must have a particular maximum viscosity at low temperatures. The lower the “W” number the better the cold temperature.

The 40 in a 20w-40 means that the oil must fall within the specified viscosity range at 100°C (minimum). Actually, it’s a fixed limit and all oils ending in 40 must acquire these limits.

20w40 is thicker at higher temperatures (normal engine operating conditions) than 10w40. High viscosity is desirable for proper lubrication at operating temperatures. So 20w40 will be better than 10w40 under normal operating conditions.

In contrast, when the bike works for a long time in extreme heat, the amount of heat generated is huge. Now here, we need to understand that liquids become thinner at higher temperatures. Hence, here we need thick oil. To counter the effect of dilution we need a thicker oil that is thick enough to cover the engine at higher temperatures.

10W40 Motorcycle Oil Castrol

Castro 10w40 motorcycle oil contains race-proven additives that save your motorcycle’s hard-working equipment. Also, it can increase your reading excitement and performance while protecting three important engine areas.

Mainly, this oil is a premium, synthetic, advanced engine oil formulated for 4-stroke motorcycles. It has been proven to provide maximum acceleration at the touch of the throttle because it flows faster. On The contrary, it can reduce internal engine friction.

Therefore, it has amazing shear stability that can prevent viscosity breakdown. But there are many types of Castrol motorcycle oil, find out which oil is best for your motorcycle oil.

10W40 Motorcycle Oil Motul

Motul provides a broad range of lubricant products for power sports and automotive applications. In particular, Motul designed the first synthetic oil and continues to advance the technology protection, performance, and efficiency.

Moreover, Motul can resist maximum oil film at very high temperatures. Besides this, it can reduce engine wear and tear. Likewise, Motul 10w40 motorcycle oil is recommended for motorcycles with all-time catalytic converters.

Yet, this 100% synthetic ester-based motorcycle oil is best to use for high-performance, off-road, sport motorcycles. Furthermore, the ester material anti-wear additives provide better shear resistance for engine reliability. Compatible with unique emission control technology, including gas treatment systems like exhaust air injection and catalytic converters.

10W40 Motorcycle Oil in Honda

Honda has developed an additive package specifically designed for the special requirements of the motorcycle engine. It has improved shear resistance, stability, and cleanliness to meet the viscosity and pressure requirements.

10w40 motorcycle oil in Honda provides excellent shear resistance, purity, and viscosity stability. Subsequently, this motorcycle oil also shortens the engine’s time to reach top speed and provides the engine’s full power output.

Usually, the patented technology was established for motorsports. Most importantly, this 10w40 motorcycle oil ensures maximum motor performance without compromising your engine life. Specifically, they come for Honda sports bikes both with oil bath clutch and dry clutch.

Read About : Honda Ruckus Oil Change

FAQ ( Frequently Asked Questions):

Q.Is 10w40 motorcycle oil the same as 10w40 car oil?

No, 10w40 motorcycle oil isn’t the same as 10w40 car oil. The main difference is the amount of zinc. Car oil 10w40 creates your motorcycle clutch slip.

Q. What is the difference between 10w 40 vs 20w 40 engine oil?

10w-40 means a viscosity of 10 when the weather is cold and a viscosity of 40 when the weather is hot. Similarly, viscosity is 20 when cold and 40 when hot. 10w-40 may give better performance than 20w-40 oil.

Q. Is 10w40 good for motorcycles?

Basically, 10w40 motorcycle oil helps to provide an amazing performance level in today’s high-performance motorcycles. Generally, it helps to keep 4-stroke engines clean. Without it, it protects your engine under extreme operating temperatures.

Q. What is the best 10W-40 motorcycle oil?

Castrol, Liqui Moly, Motul, Shell, and more motor oil are the best 10w40 motorcycle oils. Ergo, you can use them on your motorcycle suitably.

Final Word

In summary, the proper oil ensures optimal performance for your motorcycles. From our discussion, we know that the 10w40 motorcycle would provide better fuel economy. Even so, 10w40 motor oil is more suitable for a broad range of weather conditions.

Alternatively, 20w40 motor oil is best for warmer climates. Always choosing the recommended oil for your motorcycle is a good idea. We hope our analysis will help you to know about different motorcycle oils and their characteristics.

Read Also : 10W40 vs 10W60 Motorcycle Oil


I am Engr. Z Eusuf Lubricant Specialist, Mechanical Engineer & has been working with engine lubricants for a long time and knows what makes them work best. I can help you find the right oil for your needs, and I have tips on how to keep your engine running at its best.