Can You Mix 10w30 And 5w30? How To Do It Properly?

Motor oil is important for your vehicle and functions for only one mission: to keep your engine lubricated.

When mixing two different types of oil, understanding their distinct features is essential, be it a lighter oil or a denser one. One example is 10w30 and 5w30. Can you mix 10w30 and 5w30? 

It’s not recommended to combine two types of oils together, but many people still do that. How does it affect the engine performance or transmission? 

In this guide, we will instruct you on how to mix two types, such as mixing 10w30 and 5w30, so that your vehicle still works properly. Keep on reading to discover!

Can You Mix 5w30 With 10w30?

Can You Mix 5w30 With 10w30

Can you mix 10w30 and 5w30? The answer is yes. It is absolutely fine for your vehicle as they have pretty much the same grade of viscosity in temperature, thereby making them blend well together.

We can assure you it’s safe to combine them and won’t cause any serious problem with your engine.

Yet, you should be aware that 10w30 is denser than 5w30, though they are similar in viscosity oils and can make a perfect combination.

However, it’d be better if you could stick with 5w30 if your mechanic consulted you using it. Doing so can prevent the mixture from pumping out in cold temperatures.

One little thing to notice is that though they have the same weight, the viscosity at high temps will be different when operating in colder temperatures, like in winter.

The result is that the thinner viscosity in oil types makes the flow to the top ends.

All in all, it’s possible to blend them. However, to reach the most benefit for your car, only go for the one your manual recommends.

How To Mix 10w30 and 5w30

Can I mix 5w30 with 10w30? Yes, if you get the know-how. When mixing the two types of oil in different weights, the technique is to pour the light one into the engine first, so here goes the 5w30.

Next, add the heavier one – 10w30 on the top, above the light oils. This way, it will allow the motor oils to be mixed properly.

There’s one thing that you should avoid doing is mixing synthetic oils and conventional ones. 

It is important to examine the weights of engine oils that you are going to add, and they should be similar in weight so that they can run at the same rate.

The weather is also a key factor when you consider its correct weight, or you will damage the engine.

What Happens When You Mix 5W30 with 10W30?

Mixing 10w30 and 5w30 will cause no damage to your vehicle. It’s just you not getting the whole benefits of 5w30.

Technically, the texture is more like the 10w30 and has nothing different about the rating indication.

To those new to those terms, the number 30 is the exact weight of motor oil when you run the car at its activated temperatures. And the number on the front is the cold climate.

When it is in the winter, the temperature is low. So, the viscosity will change, and some parts of the engine will not have proper function.

As mentioned, the 10w30 has more density than the 5w30, so you have to be alert that the flow will end up at the top when it’s in the cold season. Besides, you can choose the 10w30 for carrying heavy loads.

In short, it causes no trouble to add those two together and still works efficiently as normal. You just can’t benefit from the warranty anymore.

Does Mixing 5W30 with 10W30 Affect Your Engine?

As we mentioned, it will just not be dangerous to mix the two types, but still, this mixture is likely to decrease the performance of your engine over time.

Also, it takes a shorter period of time for the oil change interval.

The problem here is the additives in motor oil, which will not combine well with other additives. The result is it’s hard to take in the potential of the two types to the fullest.

Especially in winter seasons, there’ll be a large difference in the viscosities, so the engine components will not blend well together.

While the heavier one, like the 10W30, will work better for carrying strong loads in cold weather, the 5w30 will be ideal for bringing more lubrication to your engine.

When you understand the strong point of each type and apply it for your different purposes, you can take full advantage of them.

However, it can sacrifice your warranty coverage if you don’t do as the manual recommends. It can be troublesome when some unexpected event occurs to your car.

Can I Mix 10w 30 With 5w 30: Try Out Our Tips

Using An Additive

An oil additive is a common type when mixing two different types. Firstly, the additive will make the heavier oil in weight move faster in the system. Then it can be compatible with the lighter one.

One more beneficial effect of using the additive is it helps prevent the engine from wear and tear.

As most additives are formed from synthetic materials, they will aim for protection and make the engine run smoothly over time.

One little note for you once using an oil additive is choosing the right one for the proper grades of oil you will use. It is easy to understand that synthetic additives should enhance synthetic oil.

As such, using mineral-based oil should be considered pairing with a mineral-based additive so that they can blend well. If it is not appropriate, your engine can be damaged.

A Few Tips To Help

There are certain rules when you want to mix two types together, and they are as follows:

  • You should be sure about the weight of oil when mixing, and it has to be similar in weight. In other words, the two should be both light or heavy. There’s no exception. If you mix them with a dramatic gap in weight, your engine will not work smoothly as it’s supposed to.
  • Using an additive should follow the suggested direction. Adding an additive can improve the two types of blends, but if you fail this, the side effect can be serious, leading to engine failure.
  • Remember to examine its level when you have completed the mixing step. Before starting your car right away, look at the level in case you can see there’s not enough oil weight inside the tank. It would help if you went with the level recommended by the manual.
  • Don’t let the oil spill when mixing, as this will lead to a burning oil smell through vents in your car.

If you are still afraid of something, let’s ask a mechanic for help. He will have a safe way to mix them successfully.


What Is The Difference Between 5w30 And 10w30?

Throughout our article, we have ascertained that the difference in density is the key to defining them.

For efficient use in cold weather, the lighter and thinner 5w30 can work wonders and help every part of your engine run smoothly when it is freezing.

On the other hand, 10w30 is way heavier and denser, so you can use it for high-capacity loads.

Are You Allowed To Blend Two Different Oils In Weight?

It is a No. Your private vehicles can not function well when you mix different weights of oils.

Yet, there’s a way to mix engine oils by combining the different viscosity levels in oils that came from the same brand.

Is it Safe to Mix 10w40 With 10w30?

Yes, it is acceptable to mix 10w40 and 10w30, except for extreme low weather. However, mixing these two oils is not advisable as they will increase the oil pressure once it corners at high revs.

Why Are Drivers Likely to Blend Motor Oils? 

Sometimes, you run low on oils, and it’s hard for you to look for the same brand you have been pouring, or maybe you want to change something new for your vehicle.

In many chances, you will end up refilling a different regular one when you run out of old oil on the way to your destination.

Your car still works properly at that time, provided that you comply with the rule.

If you want to try something new other than the old one suggested by the manual, it’d be better to consider whether it is similar or at least comparable to the old one.

Otherwise, some adverse effects can happen to your car.


How To Mix 10w30 and 5w30

Can you mix 10w30 and 5w30? This is a common question when it comes to refilling new oil to your engine. It can be another popular question apart from mixing ethanol and non-ethanol gas in cars.

As we explain the difference between the two oils, we hope you can find the answer. Mixing the different types of oil viscosity is not advisable, but doing it still does no harm to your healthy engine.

The difference between them is not so significant, so you can blend them safely and easily

You can use additives to make them combine better and ask the manufacturer if needed.

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