Skip to Content

Can Power Steering Fluid Be Used As Brake Fluid?

Can Power Steering Fluid Be Used As Brake Fluid?

People are using different fluids for their vehicles like transmission, power steering, and brake. These are necessary for its appropriate functioning and maintenance of lubrication.

Can Power Steering Fluid Be Used As Brake Fluid? You can not put the power steering fluid in brake fluid because they are petroleum-based, and it will damage the rubber parts and cause leakage. It also has a high temperature which can also damage the parts of the brake system. It can also cause compressibility in the brake system, which allows the air to entrap between them. 

Both lubricants are necessary to optimize the performance of your vehicle. These are also necessary to prevent accidents because they control the wheel’s movement and stopping the vehicle by disengaging the braking pads.

What are the purpose of power steering and brake fluid?

It is the liquid that you can add to lubricate your vehicle correctly. You are adding it for smooth driving on roads.

It will also enhance the control or alignment of the steering wheel and front wheel. When this level is low, it is hard to move the steering, producing uneven sounds.

It is also helpful to maintain the working of hoses, valves, and steering of your truck. It will also prevent corrosion on its different parts due to lubrication.

You need to change it after months because dust and grime accumulated in them make driving hard.

You can refill it by locating the reservoir near the engine compartment with a black cap.

Brake lubricant is also the type of hydraulic fluid you can use to lubricate the parts of the braking system, like rotors and pads.

 It is beneficial for the smooth running and efficient functioning of hydraulic clutch and brakes. When you are applying force through the pedal, it will allow the movement of the piston into the master cylinder.

This master cylinder will provide the liquid to the brake system and the discs present in them. Its low level produces a vibrating sound when you are stopping your vehicle.

Why you should not use a power steering fluid for brakes?

Some vehicles are equipped with an automatic power steering system that does not require any lubricant to work correctly.

Moreover, other ones will need proper lubrication for their excellent working. However, you can’t add them in brake lubricant for different reasons that can ultimately damage your vehicle.

Composition difference

It contains 85% to 95% of lubrication with 5% to 10% additives. Most of the power steering lubricants are mineral oil, silicone-based, and petroleum-based.

Some of them also contain synthetic oil with the addition of some additives to prevent them from rusting. You can also use transmission fluids for them because they are also petroleum-based. These oils are an essential component in them to reduce friction and to increase pressure.

The brake lubricants contain 70% to 80% of solvents, 10% to 20% lubricants, and 5% to 6% additives. These also have differences in composition; their main component is glycol-ether. In addition, it generally contains a mixture of glycerin and alcohol.

Some of the lubricating mixtures are silicon types that are not beneficial for proper absorbing of moisture. However, many people are still using them frequently because they prevent the pain and other parts of the vehicle from corrosion.

I’m using glycol-based lubricating liquids; their main ingredient is glycol ethylene, a good greasing agent for rubber.

Working principle

You can’t interchange or mix them because of their different working principle.

The power steering fluid provides a powerful medium for the application of pressure. It will exert force on the front wheel when the pressure moves from hydraulic cylinders to the piston.

The whole system consists of both metal and non-metal parts. So, you can use them to provide the proper friction and contact between the metal and non-metal parts.

In addition, this lubricating mixture is only beneficial for dynamic steering.

The brake liquid is generally helpful for the efficient application of brakes. For example, you suddenly need to stop your vehicle when driving on a smooth road at high speed.

When you are applying the force on the pedal to stop the vehicle, this liquid will convert this force into pressure and ultimately stops your vehicle.

These are available in different types in the market, which includes:

  • DOT 3.
  • DOT 4.
  • DOT 5.
  • DOT 5.1.

The working principle of this mixture is not only to provide lubrication, but it can also absorb the extra moisture. Moisture absorbance will prevent its part and paint surface from corrosion.

Color difference

You can’t interchange both of them accidentally or consciously during an emergency condition. Both of the liquids have different colors that you can easily recognize.

The brake fluid color is light yellow to pale yellow when you are freshly filling them in the reservoir. It will change its color sometimes due to the accumulation of impurities like dust, dirt, and grime.

The color changes also occur because they absorb moisture from the braking system, which turns them into a brownish mustard shade.

Due to impurities, its color changes from light yellow to amber and dark brown. You need to change them according to the working and the type of vehicle to prevent vibration.

The color of the power steering wheel ranges from yellowish-brown to dark brown or amber to freshly pink. After sometimes it will change its color and produce a milky and foamy shade due to contamination with water.

When you add the wrong liquid to them, it will also turn orange, indicating the appropriate one.

If you do not change it for a long time, their shade will become brown to blackish brown and this is not suitable for your truck.

Lubrication difference

You can’t say both the mixtures are the same and can be interchangeable. There is a considerable difference between their lubrication due to its several parts.

The power steering fluid is a good lubricant that minimizes the friction between its metal and non-metal parts.

Its primary purpose is to prevent abrasion during driving and ultimately prevent wear and tear. It will also protect its internal component like bushings and other accessories from unnecessary damage.

The brake liquid is not an excellent lubricating mixture as the power steering has. Its primary purpose is to reduce the moisture content from surroundings, so the brakes work efficiently.

Moreover, they are very corrosive if they accidentally spill on the metal surface, clean them quickly as soon as possible.

If they remain on the surface for some time, it can destroy the metal and eats its surface and material.

That’s why manufacturers are adding additives to protect the calipers, cylinders, and valves from rust.

Boiling point difference

The boiling point of the power steering fluid is more and is about 650-720 degrees Fahrenheit scale, and its freezing point is low. The high temperature occurs due to heavy driving at high speed on bumpy roads so that you can drive at low speed with better consistency.

It will also occur due to pinching of the line, which can cause a backup of pressure to the system, which eventually overheats the liquid.

The overheating also comes due to leakage and tearing of pipes which can cause inappropriate passage of liquid to front wheels.

The low levels also cause overheating, so check its status before driving.

The boiling point of brake fluid is low, around 100 to 150 degrees centigrade. Therefore, it is necessary to use glycol-based liquids so they decrease the boiling temperature.

It is also necessary to reduce their temperature because more heat can damage their parts. In addition, the braking system contains water; it is essential to dry them. When water that remains in them boils, this high temperature damages the rotors and pads.

In addition, less heat is produced in the brake system, which is beneficial to maintain its temperature.

Viscosity difference

The power steering fluid has low viscosity, while brake liquids will dissipate more heat and have more density. Due to low viscosity, it will freeze in a cold environment. The consistency of steering lubricants is not the same all the time, while their thickness remains the same, allowing equal pressure in all pipes.

Its uniformity is not so thick, but it is slightly thin from the power steering ones. This is because the brake systems consist of thin lines through which thin lubricants flow easily.

Moreover, the density of steering lubricant is more, and it will sink when you are not driving your vehicle.


The brake fluids are incompressible; it directly exerts pressure on wheels when you apply the force to pedals.

It is incompressible because water present in it has a low boiling point, and when it begins to boil, it will produce air bubbles which get trap in the whole system. These air bubbles are difficult to remove and cause damage to the entire system.

The power steering ones are compressible, and the air is entrapped in them due to leakage and tearing. Therefore, it is necessary to flush them by using the bleeding method to remove the trapped air.

What happens when you put power steering fluid in the brake reservoir?

When you are adding them in brake fluid, it can wholly damage the system and its parts. In addition, due to its petroleum-based composition, it will damage the rubber parts produce wear and tears in them.

The petroleum and oil present in it also damages the seals of the rubber, which can cause leaking of liquid from them.

You cannot apply the brakes efficiently and face difficulty while stopping your vehicle with the damaged rubbers.

It can also cause compressibility in the system due to which water is entrapped in them and for bubbles.

You can never put them in a brake reservoir because high temperatures will melt rubber and cause a loosening of pads due to overheating.

The density of power steering liquid is also high, due to which it gets stuck to the bottom and causes difficulty in the application of brakes.

What can you do if you accidentally put the power steering fluid in the brake reservoir?

If you accidentally pour the liquid into the wrong reservoir, you have to remove them quickly to restore the damages.

You can take turkey baster to suck out the liquid from them. You can also drain them by using the proper method and drain them in a draining pan.

Suppose it remains there for a long time, then you need to change the whole hydraulic system. You can also flush the inappropriate ones and replace them with a fresh and new one.

Can you use brake fluid for power steering?

You can’t put the brake fluid in them, but you can use transmission fluid for them. This is because the power steering needs highly lubricated liquid while the lubrication of brake liquid is low.

It is also not suitable for metal parts; its corrosive nature will damage its components. In addition, it will not maintain the appropriate pressure that is needed for the power steering system.

It can also wholly damage the whole system, which includes hoses, gaskets, and pipes.

Related Articles:

Is it easy to check the power steering fluid in the Ford F150?

How do you add transmission fluid in the new Ford F150?

What’s the gear ratio of famous pickup trucks?

What Size Air Mattress Fits in the Back of a Truck?