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

When it comes to cold weather and cars, people tend to have many misconceptions about what might happen to the inner components of the vehicle.

The braking system is one of them because it is easily considered one of the most important parts of any car or any other vehicle.

This is where people come to think that anything fluid-related can freeze during the winter season. They think that brake fluid might also get affected and might question if the brake fluid freeze during the winter season.

Keep reading as we discuss these things and answer these misconception questions with the data you need to understand how brake fluids actually work.

Can brake fluid freeze?

Brake fluid technically cannot freeze like water does when the temperature drops. This is due to the fact that it is oil. But there is a point of brake fluid becoming so thick that it ceases to function properly as it should. Basic mineral oil has a working point of -30°F or -22°C.

Let us make this very clear right from the beginning, the actual brake fluids will never freeze on their own in cold weather.

It is physically not possible due to the compound’s consistency and criteria. More accurately just because it is oil and not water.

In too much cold weather, not the usual weather we are used to the brake fluid can congeal or become gel-like, but this is still not enough to make it freeze. Unless we are living in the north or south pole of the earth, we will not be having the issue of our car’s brake fluid freezing.

If other materials come into the brake fluids, for example, DOT 3 and DOT 4 types of brake fluids absorb moisture. This in turn makes their freezing point much higher than when they are not contaminated with other fluids.

Therefore, we can conclude that brake fluids will not freeze under normal circumstances even if the cold weather sets in unless the brake lines are externally affected.

Does cold weather affect brake fluid?

During the cold, a lot of things tend to not work and cause issues. In this case, people tend to think that anything that requires fluids to work properly will also cease to work.

That is because they think the cold will make the fluid solid due to the cold weather effect.

That is where the misconception of cold weather affecting brake fluid comes in. To say blatantly, unless we are planning to go the north pole and search for Santa Claus with our vehicles. We do not need to worry about the brake fluid freezing.

Brake fluids are oil base fluids; thus, they do not freeze just because it gets cold. The freezing point of such compounds is usually around -40°F or -40°C.

Under normal circumstances when cold weather comes, the brake fluids just get thicker but do not become solid.

What happens to brake fluid when it gets cold?

Since we understand that the brake fluid will not freeze when the cold weather sets in. But some things will happen if the temperature drops low other than freezing. Let’s understand those things below.

Weaken Brake Lines:

When it gets cold the quality of health of our brake fluid will get.

If this situation continues and the fluids continue to get exposed to such harsh elements then it will make our brake lines wear out over time as well as form cracks and tears.


When it gets cold the brakes will be fine unless we find ourselves in the temperatures -40°C then it starts to congeal. This temperature does not make the fluids into icicles either.

However, congealing is not better than freezing since our cars will not be able to brake properly. When congealing happens, the brakes will make grinding and squealing sounds during driving.

Malfunctioning ABS:

Due to the fluid becoming gel-like and thicker the brakes will stop functioning normally.

Thus, us slamming on the brakes will make the car unintentionally the emergency braking system activate randomly.

What temperature does brake fluid freeze?

Brake fluid can be of three types, these are DOT3, DOT4, and DOT5. There is little difference between DOT3 and DOT4 as both of them are glycol-based fluids, they are hygroscopic. This means that these fluids will absorb moisture.

Normally these fluids will congeal or become gel at temperatures of -40°F or -40°C.

However, if they are contaminated with water because over time they will absorb water, then this point of temperature will be much higher as the fluid will not be just oil-based anymore.

On the other hand, DOT5 fluids are silicone-based brake fluids and this one does not absorb water and so the freezing point of this brake fluid while remaining the same as the two above, it does not fluctuate due to absorbing moisture.

Regardless of the temperature brake fluids do not reach a solid freezing stage. Unless we are facing arctic temperatures.

What to do when brake fluid freezes?

We have established that brake fluids do not freeze under normal circumstances and only if you go to the north pole you might need to worry about it freezing. However, if you happen to find yourself either visiting or living in Yakutsk, a city in Russia.

That city is considered the coldest in the world. Temperatures regularly drop around -40°F or -40°C. Then you need to know what to do when the brake fluid freezes.

Start the Car:

Keep trying to start the car, apparently, people in cold areas like Yakutsk, leave their car engine running.

This is because at temperatures like that we have to worry about more than our brake fluids freezing, like the battery and carburetor.

Once you start the car and keep it running, the heat produced from the engine throughout the vehicle will slowly melt and normalize the brake fluids.

Go back and forth:

After the successful start of the vehicle keep going back and forth and try repeatedly applying and releasing the parking brake. This will loosen the vehicle brake lines.

Can old brake fluid freeze?

When brake fluid becomes old it usually becomes contaminated and dirty. This will affect how we drive our vehicles as it will disrupt our braking systems. The brake pedal will feel stiffer.

Over some time moisture will be the cause of internal corrosion in the brake lines, the master cylinder, calipers as well as other components.

There are a lot of things an old brake fluid does that relatively new brake fluid will not do. However, one thing is for certain, even if the age of the brake fluid is higher than usual. That still will not freeze under cold temperatures.

Can brake lines freeze?

Brake lines contain brake fluids in them and they do not freeze like water does during cold weather. Brake lines will not freeze even in the coldest of winters. Only if they are contaminated, they will congeal in higher temperatures than normal.

However, if we are talking about becoming frozen solid, this is not happening unless we find ourselves living in the arctic areas of the earth. This is because brake fluids that are present in the brake lines are oils.

At what temperature do brake lines freeze?

Brake lines are filled with brake fluids that are not usually frozen during even the coldest of winter.

Brake lines unless contaminated will stay as usual as the normal temperature of a brake fluid becoming like gel is around -40°F or -40°C. They will not freeze and become icicles as water would.

Temperatures below -32°F are not normal in most regions. That is why we do not need to worry about the brake fluid becoming gel and freezing is out of the question anyway.

Final thoughts

The standard brake fluid is made from a mixture of glycerin and alcohol known as glycol as well as extra additives that gives it the oil-like properties it needs. This in turn gives it attributes that make the chemical solution not freeze even in the most cold weather we could think of.