Motor oil is essential to your vehicle. Every motor oil is considered to be the bloodline of your engine. To avoid future damage and engine failure, you need to pick the right and suitable motor oil for your vehicle.
It also has something to do with the viscosity of every motor oil. Every engine needs a certain level of viscosity. As a car driver, you should know very well what is the right motor oil for your engine.
So now, we are going to talk about 10w40 motor oil and 15w40 motor oil. This article will discuss the differences between 10w40 motor oil and 15w40 motor oil and if you can swap them both. Let us get started.
Table of Contents
What Is the Difference Between 10w40 and 15w40 Oil?
Every motor oil is different because of its viscosity. The car is new, and the area is cold, use 15w40 have their differences and similarities. Let us know the differences between 10w40 motor oil and 15w40 motor oil in terms of fuel economy, hot weather, and viscosity.
Viscosity
The motor oil grade means the weight of the motor oil if it is in the cold and in operating temperatures. This is because the viscosity of the motor oils will increase with the rise of the temperature too.
For example, a 10w40 motor oil will get thicker in cold weather than the 15w40 motor oil. However, both of them will have the same viscosity in high temperatures.
Fuel Economy
A 10w40 motor oil is known to break down faster than the 15w40 motor oil. The reason behind this is that the 10w40 motor oil has more viscosity indexes. But it is said that this statement holds no truth in it.
This is the enemy of most engines today because it significantly reduces the longevity of the vehicles. There will also be some sludges. There is not much information regarding the fuel economy.
The car is new, and the area is cold, use 15w40. You have to stick with the recommended motor oil for your engine because the manufacturer knows what is best for your engine in terms of fuel economy.
Hot Weather
The 15w40 motor oil can be used both in temperatures. The number fifteen in the name of the motor oil does not mean that the low temperature will limit to fifteen.
The lower the first number is, the lower will also be the temperature. More fluid will also be in the oil. In cold weather, it is advisable to use thicker oil. The 15w40 motor oil will be the best choice.
Can I Use 10w40 Instead of 15w40?
This depends on many things. You can use 10w40 motor oil instead of 15w40 motor oil, but you have to know that your manufacturer should always use the recommended oil. The winter viscosity number will state the cold start performance.
The low number will dictate that the motor oil will be thin and have less static friction in the engine. As a result, the 10w40 motor oil will perform better in cold starts, much better than the 15w40 motor oil. The 10w40 motor oil will also get thicker than the 5w40 motor oil if it is cold.
Accidentally Used 10w40 Instead of 15w40: Is It Ok?
The fifty-grade oil has a high viscosity at one hundred degrees Celsius in less than forty-grade oil. Therefore, the 15w40 motor oil will be thicker at cold temperatures than the 10w40 motor oil. This means that it will flow much worse on startup.
The 15w40 motor oil can be used in diesel trucks, farm tractors, passenger cars, and other equipment. The rule of thumb is to use the recommended motor oil for your vehicle.
10w40 vs 15w40 High Mileage
A 10w40 motor oil is recommended to be used for high mileage vehicles. The 10w40 motor oil is more vicious and thicker and thicker oils will help older engines to handle high temperatures and even manage to avoid wear and tear.
If the motor oil will be thicker, it will reduce more tear and wear and provide an extension to the life of your engine. On the other hand, 10w50 motor oil is recommended for vehicles with high mileage that have an approximate sixty thousand (60,000) miles and more.
Which Is Better, 10w40 or 15w40 Oil?
This will depend on some things. First, you must consider the vehicle that you are using and the conditions of your driving. Second, the best motor oil for your engine is the motor oil that your manufacturer recommends.
When Should I Use 10w40 And When 15w40?
If you are driving in high temperatures and it is more excellent than ninety degrees Fahrenheit, you can use the 10w40 motor oil. The 10w40 motor oil can work in temperatures as high as one hundred four Fahrenheit.
On the other hand, the 10w30 motor oil’s maximum working temperature is eighty-five degrees Fahrenheit. Still, you should refer to your owner’s manual.
10w40 vs. 15w40 Toyota
The recommended oil for all Toyota engines is 5w30 motor oil. However, the 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil.
10w40 vs. 15w40 Nissan
The recommended motor oil for Nissan vehicles is 5w30 and 10w30. However, the 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil. Still, you should refer to your owner’s manual.
10w40 vs. 15w40 Subaru
The recommended motor oil for all Subaru engines is 0w20 and 5w30. However, the 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil.
10w40 vs. 15w40 Mazda
Almost all the vehicles and SUVs of Mazda will need 0w20 motor oil. On the other hand, the 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil. But, refer to your owner’s manual for the right motor oil.
10w40 vs. 15w40 BMW
For all BMW engines, they are recommending 5w30 motor oil. However, the 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil. Still, you should refer to your owner’s manual.
10w40 vs. 15w40 Ford
According to the 2020 ford owner’s manual, almost all of their engines must be using a 5w30 motor oil or 0w30 motor oil. The 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil.
10w40 vs 15w40 Chevrolet
For Chevrolet, the recommended oil is 5w20, 5w30, or 10w30 in some engines. However, the 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil. But, refer to your owner’s manual for the right motor oil.
10w40 vs. 15w40 Jeep
The recommended viscosity for jeep vehicles is 0W20, 5W20, 5W30, or 10W30. The 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines.
If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil. If your vehicle is new and has a cold area, you can use 15w40 motor oil. Still, you should refer to your owner’s manual.
10w40 vs. 15w40 Volkswagen
Their recommendation is only 5w30 and 0w20. The 10w40 motor oil and the 15w40 motor oil are not in the recommended list of motor oils for Toyota engines. If you are driving in high temperatures, like more than ninety degrees Fahrenheit, you can use 10w40 motor oil.
If your vehicle is new and has a cold area, you can use 15w40 motor oil. But, refer to your owner’s manual for the right motor oil.
Summary
In summary, knowing the right motor oil for your engine is a vital part of keeping your vehicle and its engine in good condition. Having motor oil for your engine is essential, but it is more essential to put the right motor oil, especially viscosity.
You have to refer to your owner’s manual for the right motor oil. They are the ones who know the suitable oil for your vehicle.
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