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Can You Mix Brake Fluid? (All You Need to Know)

If you have a hydraulic braking system in a modern car, you know brake fluid is a must-have ingredient for you. You need to use it regularly to make the brake perfect and smooth. It becomes essential and crucial when you go for a hard brake.

You can simply put some brake fluid and make the brake work for you. It will reduce the force you need to put on the brake. If you don’t use brake fluid, your car braking system will be wrong.

You will face difficulties braking smoothly. However, brake fluid has different variations. You will find DOT 1, 2,3,4,5, and 5.1. These are the most popular brake fluid in the market. Sometimes, you might have DOT 1, and you buy DOT 4, can you mix them?

That’s the challenge most drivers face. They want a clear solution to sort out the issues. So they ask whether you can mix brake fluid.

Can you mix brake fluid?

You can mix brake fluid. But, there are some pre-conditions. If you want to mix brake fluid, you should know which fluids are interchangeable. You cannot mix the fluid randomly. They will come with the interchangeable fluid; you can indeed mix and use them simultaneously if you buy them.

Moreover, different categories of brake fluids are there. You cannot mix them in most cases, except dot 3 and dot 4. Additionally, we also find other fluids that can be mixed. Therefore, it is ok to mix brake fluids.

It’s time to know which combination of fluid you can mix properly. We come up with four different varieties that people mostly want to know about.

Synthetic with regular:

You cannot mix synthetic with regular brake fluid. They will be of no use. Because of two different ingredients, you should not mix them. You only mix the same ingredients, for instance, synthetic with synthetic and regular with regular.

Regular brake fluid doesn’t contain any synthetic oil material; therefore, you cannot mix the synthetic with regular oil brake.

Dot 3 with dot 4:

You can mix Dot 3 with dot 4 brake fluid. They come with similar ingredients. They belong to the same family of brake fluids. That’s the main reason why you can make a mixture of these brake fluids.

Glycol is the main ingredient for these two brake fluids. Therefore, they will dissolve and make the regular brake fluid when you mix them. And, you can surely use them on your braking system.

Mineral with synthetic:

You can mix minerals with synthetic oil. That will be fine. Mineral-based brake fluid and synthetic-based oil are compatible. Here the mineral plays a crucial role and lets synthetic win.

On the other hand, you can mix minerals with other ingredients like synthetic oil. So, it will be safe and sound to mix minerals with synthetic brake fluids. Your braking system will also absorb the mixture properly, so no worries.

Synthetic with non-synthetic:

You can safely mix synthetic and non-synthetic brake fluids. That will be fine. Moreover, the synthetic and non-synthetic are entirely compatible with one another.

However, you will not get the best performance from the mixture. Synthetic oil will lose its quality and become a medium-quality brake fluid. That’s why you should not mix them. And, it is ok to mix brake fluid.

So far, these are the most available brake fluids that you can use in your braking system. However, You need to avoid using synthetic and regular oil-based brake fluid. They are not compatible with each other. They will react and lose the quality.

Can different brands of brake fluid be mixed? Can you mix old and new brake fluid?

Brands can’t play any big role in mixing different brake fluids. You can surely mix different fluid brands with similar ingredients; it will be ok to mix them.

Mostly, brands come with synthetic oil brake fluids, which means other brands of brake fluid can be mixed.

On the other hand, you cannot mix the same brand brake fluids if they come with different ingredients like synthetic and regular. That will be a mess, and nothing will work in that case.

So the main part is the similar ingredients. If you buy the different brands of brake fluids that come with similar ingredients, you can mix them and enjoy applying them to the braking system. But you cannot mix old and new brake fluids.

Will mixing different types of brake fluid ruin my master cylinder?

Mixing different types of brake fluid will not ruin your master cylinder. It will be safe and sound. However, you should avoid mixing synthetic and regular fluid. Otherwise, it will hamper your braking system.

The Master cylinder doesn’t get destroyed or damaged due to the mixture of different types of brake fluids. You can simply mix the dot 3 and dot 4 or similar brake fluids. They will not do any damage to your master cylinder. You will love their services.

What happens if you mix brake fluid?

If you mix brake fluid, they will dissolve or mix each other in most cases. However, they might do something else. What happens if you mix brake fluids?

Become regular:

If you mix dot 3 & 4 brake fluids, they will mix properly and become a regular brake fluid. They will not react or do any harm to your vehicle at all. They will increase the overall performance.

Exchange ingredients:

If you mix brake fluid, they will surely exchange their ingredients.

Let’s say you mix synthetic oil brake fluid with mineral oil. In that case, synthetic oil will devour mineral oil. Therefore, mineral oil activities will not be there anymore.

React adversely:

When you mix different brake fluids, they will react if you don’t mix similar or non-reactive brake fluids. Especially if you mix synthetic oil with regular brake fluid, they will not be effective anymore. However, you cannot expect to use it for better performance.

One will lose effectiveness:

If you mix brake fluids, one will lose its effectiveness, and the other will fill the gap. That’s the ultimate thing that will happen.

So, you should mix similar types of brake fluids. So, the ingredients will mix properly and become one of the best brake fluids. On the other hand, you should avoid mixing brake fluids since the practice is not ideal.

What types of brake fluids can be mixed? Which brake fluids are interchangeable?

Different types of brake fluids available can be mixed. We will talk about them. Before that, let’s see which brake fluids are interchangeable.

DOT 3, DOT 4, and DOT 5.1 are all interchangeable brake fluids. You can mix them and get the best brake fluid indeed. However, there might be other interchangeable fluids as well. But, till now they are the best.

Synthetic Brake Fluids:

Most synthetic brake fluids can be interchangeable, and you can also mix them. However, you can also mix synthetic brake fluid and non-synthetic brake fluids.

DOT 3, 4, & 5.1:

These three are the best interchangeable brake fluids. You can mix them and enjoy the best performance as well. They don’t lose any quality.

Minerals brake fluid:

You can surely mix minerals brake fluid without having any second thoughts. You can mix other brake fluids with the minerals brake fluid. It will be fine with your braking system.

These three are the best brake fluids that you can mix. They don’t lose any quality and damage your braking system and cylinder. Therefore, you can go for them and use them in your braking system.

DOT 3,4, and 5.1 are interchangeable and compatible brake fluids among these three brake fluids. They have similar ingredients which are compatible too. On the other hand, all three brake fluids are compatible.

What happens if you mix synthetic brake fluid with regular brake fluid?

Regular brake fluids come with glycol-based oil that is not compatible with synthetic brake fluids. Therefore, you cannot expect to mix and use them for a long time. One of the main reasons is the ingredients.

Different braking fluids have different ingredients. Glycogen is the regular fluid, whereas synthetic is another fluid ingredient. Both are good for the brake system.

But you should not mix them. They will lose their quality and decrease the performance indeed. Therefore, you should avoid mixing them and use them separately.

So, the ultimate advice is to use the regular fluid or synthetic-based brake fluid. They are better in separate uses. If you mix them, they will react and not meet your requirements.

Final Thoughts

DOT 3, 4 & 5.1 are the best compatible brake fluids. You can securely mix them and use them in your braking system if you have them. On the other hand, if you want to use synthetic oil brake fluid, you should avoid mixing any other brake fluid with it. It will become a mess and won’t do any good.