Updated at: 10-03-2022 - By: micdot

Diesel engines and police patrols typically use 5w30 motor oil. In terms of viscosity grades, a 5w30 motor oil is a multi-graded oil that ranges in viscosity from 30 to 5. (5). According to the Society for Automotive Engineers, or SAE, 5w40 is a motor oil that has been tested by the SAE.

These two types of motor lubricants have long been interchanged by motorists. We’ll clear up all of these misunderstandings now. 5w30 vs. 5w40 motor oil comparisons will be the focus of today’s topic. It is time to get started.

What Is the Difference Between 5w30 and 5w40 Oil?

Viscosity of 5w30motor oil is low. Winter is denoted by the win the 5w30, and the number corresponding to its viscosity at high temperatures is represented by this number. The Society of Automotive Engineers (SAE) has devised a numerical code system for rating engine oil. The 5w40 motor oil helps the engine run smoothly and reduces any overheating in the moving parts by absorbing heat from the engine. Because of the thicker viscosity of 5w40 motor oil, combustion heat cannot escape. The viscosity, temperature, and fuel economy of these two oils have been compared, therefore it’s time to examine the differences.


Viscosity is a key difference between the two oils, and 5w40 motor oil has a higher viscosity than 5w30 motor oil. This suggests that the 5w30 motor oil is superior to the 5w40 motor oil in terms of performance and longevity. Low viscosity lubricant with high viscosity is the 5w30 motor oil (30).

The viscosity and weight of the engine are indicated by the 5w40 motor oil. Viscosity ranges from five (5) to forty (40). (40). It is also thicker due to its low viscosity. As a result of its high viscosity, the 5w40 motor oil will not be a thick paste. This is determined by the flow of the engine’s liquids.

Fuel Economy

Because the 5w30 motor oil has a high pressure but a low flow, it will easily enter the engine. 5w30 motor oil is significantly more fuel-efficient than 5w40 motor oil when it comes to fuel efficiency. These motor oils can be used in a wide range of automobiles.

Hot Weather

The viscosity of the 5w30 motor oil is lower. As a result, it’s more suited for use in hot or cold climates. The viscosity of 5w40 motor oil is higher.

As a result, it cannot be used in all climates. Use of the 5w30 motor oil at cold temperatures is possible due to its multi-grade design. This oil is made from crude oil and can be used in both unleaded and leaded gasoline vehicles. Use of 5340 motor oil extends from -250 degrees Celsius to 350 degrees Celsius. When used in temperatures ranging from -250 to 350 degrees Celsius, 5w30 motor oil, on the other hand, will perform admirably.

Can I Use 5w30 Instead of 5w40?

Your vehicle’s duty cycle will determine how often you should change your oil. Towing, stop-and-go traffic, and residing in a hot climate can all cause problems. It will thin considerably more if heated, making the motor oil even thinner.

Metal-to-metal contact will occur if the oil film is damaged. More heat will be generated in your engine as a result of this contact. A stop or start technology in your car may cause some wear in your bearings since it takes longer for the motor oil to reach them. When using 5w40 oil, you will need a larger oil pump than if you were using 5w30. Your drain interval will be shortened if your car is a European model with an extended drain interval.

Accidentally Used 5w30 Instead of 5w40: Is It Ok?

The answer is yes. In order to have oil flowing into all of the engine’s critical components, you must ensure that the oil pump is creating sufficient pressure. Everything will be OK if that is the case. If the oil pressure light doesn’t come on while you’re idling, there’s nothing wrong with your vehicle. It will only work if the oil pump is able to deliver the required pressure. Some people claim that because the 5w40 motor oil has a VW specification, it could be problematic. In addition, the additives are not prevalent either.

For those who are concerned, an oil change is an option. However, the likelihood and severity of the harm are quite minimal. Depending on the engine, some claim it’s fine as well.

15w40 vs 5w30 High Mileage

It’s preferable to use a 5w30 motor oil in automobiles with a high mileage. Mechanics, on the other hand, support high mileage engines with 5w40 motor oil. For this reason, you should only use this type of engine oil. The moving parts were even better lubricated as a result of the additive.

Which Is Better, 5w30 or 5w40 Oil?

The purpose of the motor oil is to reduce friction and wear on the moving elements of your engine, therefore protecting your vehicle. Many different types of motor oils are available on the market. There is a lot of debate concerning which motor oil is better: 5W30 or 5W40. As a result, both of these motor oils perform admirably. Cold weather is no problem for these products, and they’ll lubricate the engines correctly.

However, both of them are usable in temperatures over freezing. As a result, the answer to this question is that it depends on the vehicle. As a result, make sure you use the engine oil manufacturer recommends.

When Should I Use 5w30 and When 5w40?

Use the 5w30 motor oil in both hot and cold climates because of its low viscosity. The 5w40 motor oil, on the other hand, has a very high viscosity. As a result, it cannot be used in all climates. Only gasoline engines can use the 5w30 motor oil. However, only use these motor oils if they are included in your vehicle’s manufacturer’s recommended motor oils list.

5w30 vs. 5w40 Toyota

All Toyota engines should be lubricated with 5w30 motor oil. Toyota does not advocate using 5w40 motor oil in its vehicles. However, you are free to make use of it if you so desire. Performance engines in European gas-powered automobiles should use 5w40 motor oil. However, if it is indicated in the owner’s handbook, it is still the decision of the manual.

5w30 vs. 5w40 Nissan

5w30 and 10w30 are the recommended motor oils for Nissan automobiles. You can still use 5w40 despite the fact that it’s not listed in the recommended motor oil. In high-performance engines, 5w40 motor oil is the best choice for use.

5w30 vs. 5w40 Subaru

0w20 and 5w30 synthetic motor oils are suggested for Subaru engines. You can use 5w40 motor oil if you choose, although it is not recommended. Just be aware that doing so is not advised. Performance engines should use 5w40 motor oil.

5w30 vs. 5w40 Mazda

0w20 motor oil is required by nearly all Mazda automobiles and SUVs. The only thing they have going for them is a 5W-30 oil.

However, they do not recommend the 5w40 motor. It is recommended that you consult your owner’s manual before using a 5w40 motor oil, which is more commonly found in high-performance engines.

5w30 vs. 5w40 BMW

They recommend 5w30 motor oil for all BMW engines. However, even if 5w40 motor oil isn’t on their list of recommended products, it can be utilized. It is common practice to use 5w40 motor oil in high-performance automobiles.

5w30 vs. 5w40 Ford

Ford’s 2020 owner’s manual specifies that a 5w30 motor oil or a 0w30 motor oil must be used in nearly all of their engines. The 5w40 motor oil is not mentioned. It’s common with European performance engines, but always check your owner’s manual to be sure.

5w30 vs 5w40 Chevrolet

In some Chevrolet engines, 5w20, 5w30, or 10w30 is the recommended oil. 5340 motor oil isn’t mentioned anywhere. However, if you so desire, you may make use of it. In high-performance engines, 5w40 motor oil is suggested. Consult your owner’s handbook for more information.

5w30 vs. 5w40 Jeep

5W20, 5W30, 10W30 are the recommended viscosities for jeep vehicles. There’s no mention of 5w40 in their list of suggested lubricants. Performance engines are typically advised to use 5w40 motor oil.

5w30 vs. 5w40 Volkswagen

Only 5w30 and 0w20 are recommended by them. The 5w40 motor oil isn’t mentioned, so it’s best to avoid it, but you can still use it. Performance engines in European automobiles can benefit from the 5w40 motor oil.


A 5w30 motor oil can be used in place of a 5w40 motor oil in some cases. Many people have also inquired as to whether or not they may trade locations and what the differences are between the two.

The differences between 5w30 and 5w40 motor oil can be summarized as follows: However, there are some similarities between the two as well. However, always consult your owner’s handbook while deciding between the two.