Can You Mix 5W20 and 5W30? What Happens If You Mix?

Engine oil is crucial for your car. But can I mix 5w20 and 5w30? This is the famous question that comes to us. If you also want to know the answer, stay with us and keep reading.

So, can you mix 5w20 and 5w30 oil? Yes, You can combine both oils, but it’s not advisable. Primarily, your engine will support it. But actually, for mixing both oils should be the same brand, viscosity, and similar API service level to prevent engine damage.

If you mix 5w20 and 5w30, you probably get no visible results. Therefore, if you mix them to increase engine performance, you might be disappointed.

However, to learn more about the mixture of 5w20 and 5w30 without further delay, let’s get started.

What Happens When You Mix 5W20 and 5W30?

What happens in the engine if you mix both oils? To know appropriately, you need to comprehend them. As laid down by SAE, the multi-grade oil format and the “W ” letter indicate that both oils are perfect for winter and low temperatures.

The letter before the number indicates the viscosity below 0°C. And the letter of the after number refers to the consistency at 100°C. Due to 5w30 oil’s high viscosity, it’s more suitable for high temperatures. Typically, 5W20 oil provides the best performance in cold temperatures.

So the question is, what happens if you mix both oils? Whether both oils contain different viscosity and additives, you cannot thoroughly mix them to make a single oil mixture. Here oil brand is also a matter, if both oils are from a different brand then you will fall into more trouble because different oil blending recipes & additive packages are not similar. So if have to mix 5W20 & 5W30 oils for an urgent situation, try to take both oils from the same brand.

In either case, if you mix them for emergency requirements, you won’t see any immediate problem with your engine. But if you use mixing oils in your incompatible machine, your engine will damage over time.

The problems are sludge formation, overheating, deposits, and oil leaks in the engine. Therefore it’s suggested that if you use oil in your compatible machine for emergencies, using the right oil is good.

What are The Ratios Of Mixing 5w20 and 5w30 Oils?

Mixing them might be suitable for the engine, but manufacturers still discourage mixing 5w20 oil and 5w30. Nonetheless, in emergencies for the 5w30 engine, you must use heavier oil 5w30 higher than the thinner oil 5w20.

For example, you can go for both portions 5w30 and one portion 5w20 oil, in the engine 5w30 and vice versa. More importantly, check your owner’s manual to use the proper ratio if your engine uses mixing oils.

Can You Mix 5w20 and 5W30

Can I Use 5w30 Instead of 5w20?

In an engine of 5w30, it’s not a wise choice to use 5w30 oil. It’s because the engine 5w30 oil contains higher viscosity, and for the 5w20 engine, it’s too thick. For that reason, the 5w20 engine needs a thinner barrier.

Typically, if you use 5w30, the 5w20 engine tools won’t get proper oil coating to flow because of thickness. As a result, there will be wear and tear, overheating, and oil starvation.

Besides this, your engine parts would face much resistance if you use different engine oil in your 5w20 engine. Using 5w30 oil can be safe if mixing 5w20 oil in your 5w20 engines.

Check Also: Can I use 0W20 instead of 5W20?

Can I Add 5w20 to 5w30 Oil?

Yes, you can do it, making minimal problems or changes. Notably, it doesn’t affect your engine, and you cannot see any differences.

Even so, it can be safer if you can use the exact API specifications and manufacturer. Mainly, you can do this if there is no chance to get 5w30 oil. To do it, you need to change your full oil instead of topping it up.

Main Differences between 5w30 and 5w20

Eventually, 5w20 oil works at a lower temperature if compared with 5w30 oil. Still, 5w30 oil also works at low temperatures, unlike 5w20 oil. Although 5w30 oil can’t work at low temperatures, it only performs well at higher temperatures.

At lower temperatures, 5w30 can work to an extent; but not like 5w20 because of higher viscosity. On the other hand, the 5w20 oil can coat the extent parts with a thin block to the deepest parts. Thus, any engine part isn’t deprived of oil this way.

On the contrary, 5w20 oil cannot properly coat the engine’s tools because of its thinness at higher temperatures.

As a result, this engine causes wear and tear. In contrast, 5w30 oil can adequately lubricate the engine parts and prevent friction. Heat generates the engine oil more watery.

At average temperatures, 5w20 is the best option for fuel economy. The lower viscosity oil is applied because it offers a thinner barrier for the lubrication of engine parts.

Are There Any Advantages of Mixing Oils?

There are no actual advantages to mixing both oils. Some people get the benefit because of mixing oils but not permanently.

Changing the base oil in the engine needs an oil change and a new oil filter. Ergo, if you mix 5w20 with 5w30, you need to change the oil again after a few thousand miles.

FAQs (Frequently Asked Questions):

Q. Can you mix 5w30 and 10w30?

No, you can’t get any desired result by mixing both oils because both oils come in different grades. 5w30 oil is lighter, and its density is less. Whereas 10w30 is a high-grade oil and has a higher density. So, it’s not suitable if you mixed 10w30 oil with 5w30.

Q. Can I mix in 5w-30 oil with 10w-30 oil?

Yes, you can mix them. In hot temperatures, they act very similarly. Both oils have the same viscosity at operating temperature. For your 10w30 engine, you can use 5w-30 oil with a mixture.

Q. What happens if you mix 5w20 oil and 10w30?

The car manufacturer doesn’t recommend mixing different types or different grades of oil. Most drivers claim it’s safe to mix two straight-weight or multi-grade oils instead of combining multi-grade with refined-weight oils. So though there is no immediate impact of mixing 5w20 oil & 10w30, you should not do it without any urgency. If you have to do it in any case, please change the whole engine oil and refill with the recommended one as early as possible.

Q. Can two different engine oils be mixed?

Today’s synthetic oils are fully compatible with traditional oils, and you can mix them safely. But old API-graded mineral oils are not compatible to mix. Especially you should not mix different graded or different brand engine oils without any serious or temporary solution.

Check Mineral Engine Oil Vs. Synthetic

Final Word:

To conclude, for the question, can you mix 5w30 and 5w30? Yes, you can combine both of these oils. But it would help if you ensured that both oils come from the same brand. Usually, if not the same brand, it’s still also ok.

Engine oils don’t last long; that’s why changing to full oil is the best idea. Changing the entire engine oil is best if you add a different viscosity.

Note that motor oils decrease over time, and never use expired oil. Also, oil filter changing is significant. All of these tips help prevent severe damage to your engine. Thanks for staying with us.


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.

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