Updated at: 22-03-2022 - By: Lucas

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Your car’s engine can be run on a mixture of different types of motor oil. However, not all oils can be safely combined. Do 5w30 and 10w40 oil blend?

Yes, they can be combined! These oils appear to be completely distinct and act in different ways at high temperatures. If they’re both from the same company, it’s okay to mix them.

Even if the oils are from the same manufacturer, there are a slew of considerations to bear in mind before attempting to blend them.

All you need to know about blending 5w30 and 10w40 oils, regardless of brand, is covered in this article.

Is It Safe To Mix Motor Oils ?

Mixing different oils in your car’s engine is generally safe, but it won’t boost the vehicle’s performance.

When you combine two different oils, the molecules in each oil will strive to adapt to the other, reducing the efficiency of the additives in both oils.

Engine oils of any viscosity, brand, or kind should never be mixed. This just diminishes the projected benefits of each of the blended oils to your car engine.

Oil mixing, it appears, reduces the amount of time between oil changes. Even so, despite the fact that it’s legal to mix motor oils, this practice is not recommended and can potentially void new-car warranties.

Can You Mix 5w30 and 10w40 Oil?

The basic answer is YES, you can mix 5w30 and 10w40 oil without fear of catastrophic engine damage.

For this reason, it is best to use 50/50 mixtures of 5/30 and 10/40 because the viscosity and weight of the two oils are so dissimilar.

If the two oils are made by the same company, the mixture will be much superior. Also, before adding the new oil, make sure the old one is completely drained away.

It’s also worth noting that the various weights of 5w30 and 10w40 may result in oil clumps when mixed.

What Happens When You Mix 5w30 10w40?

Because 10w40 is heavier than 5w30, using both can put your engine under a lot of strain. A decrease in your car’s fuel economy is another possibility if these oils are used together.

Mixing 10W40 and 5w30 does not have any other effect other than reducing fuel economy and decreasing oil change intervals.

Nevertheless, manufacturers may prescribe a specific brand or type of oil for use in the engine of most current cars.

The warranty on your automobile will be voided and your engine may not function at its peak if you disregard our advice.

Whay More?

It’s still true that mixing motor oils won’t cause your engine to blow up or damage any of the engine’s components catastrophically.

It’s possible that your engine’s oil seals could be damaged and sludged up over time if you continue to use mixed oils. If you don’t take care of them, they can cause damage.