For some reason, you accidentally add brake fluid to the power steering pump. What happens if you put brake fluid in the power steering? Let’s revisit the topic Can you use brake fluid as power steering fluid to get an answer:
Brake Fluid and Power Steering Fluid: Are They Similar?
Our answer is “No.” These are two types of oil with completely different properties and functions, used for two separate systems in the car: the braking system and the power steering system. Let’s look at the differences between these fluids:
What is Power Steering Fluid?
Power steering fluid is a special auxiliary solution used to lubricate the hydraulic system (pump, valve) of the power steering. Power steering fluid helps the driver handle the steering wheel more easily, allowing them not to exert too much effort while still driving the vehicle accurately and smoothly. It is a petroleum-based fluid that acts as a pressure transfer fluid for the power steering and is primarily used for dynamic steering.
Power steering fluid must meet requirements such as not being compressible, not changing viscosity much when temperature changes, and not creating residue. During each maintenance session, the power steering oil should be checked and topped up if lacking.
What is Brake Fluid?
The main function of brake fluid is to absorb moisture present in the braking system. Brake fluids from lubricant manufacturers are all glycol or silicone-based and have appropriate viscosity, preventing corrosion of metals and materials in the braking system (rubber, plastic, cast iron, steel…), ensuring lubrication and a high load-bearing surface… Some important effects of your car’s brake fluid:
- Improve the safety of the braking system.
- Resists corrosion and oxidation and protects the vehicle’s braking system.
- Offering good force transmission and good flexibility even at high temperatures and high humidity.
- Ensure proper lubrication of the vehicle’s braking system, thereby enhancing the lifespan of the vehicle and the braking system.
- Improve driver safety during emergency braking.
Unlike power steering fluid, brake fluid is not a good lubricant; this fluid is used for static brakes. It is a petroleum-based fluid that acts as a pressure transfer fluid for the power steering and is primarily used for dynamic steering.
So now you had the answer to the question: Are power steering fluid and brake fluid the same thing?
Can You Use Brake Fluid for Power Steering Fluid?
Can brake fluid be used as power steering fluid? Certainly not, these fluids are not meant to be mixed or used interchangeably. They are hydraulic fluids but they have different chemical compositions. The oils themselves also have their own parameters and viscosity grades; mixing them is very dangerous or will at least damage or reduce the vehicle’s lifespan. So are there consequences related to this mistake?
Brake fluid is much more abrasive and it is alcohol-based because a petroleum-based fluid would erode the rubber seals and hoses; which would cause a system failure. Using brake fluid in the power steering system can damage the seals and other components of the power steering system. This can lead to leaks, reduced steering performance, and potential safety risks.
Whereas power steering fluid is petroleum-based and a power steering system (of the rack and pinion type) has many metal-on-metal contacts. In addition to being a pressure transfer fluid, it also functions as a lubricant. Brake fluid is not a good lubricant.
Therefore, it is appropriate to use only power steering fluid for the power steering system and brake oil for the braking system, as all automobiles offer the best performance. Although in some undesirable cases, where there are no other alternatives, brake fluid can be used as power steering fluid, it should only be a once-in-a-lifetime occurrence.
You should never use brake fluid as power steering fluid because this system requires a fluid with a high boiling point. However, you can replace power steering oil with brake fluid in some extreme situations, as both are hydraulic fluid.
What to Do If You Add Brake Fluid to the Power Steering System?
If you accidentally use brake fluid instead of power steering fluid, what should you do? It is important to know that using brake fluid in the power steering system is very dangerous. The first thing to remember is not to start your engine because as soon as you start the engine, the brake fluid flows into all the lines. What we recommend is to immediately flush all the fluid from the reservoir as soon as you notice you are using the wrong fluid.
This step would be easy if you still haven’t started your car; however, extracting or removing the fluid will be more difficult if your car’s engine has been started because by that time these fluids are already mixed. You need to open the cap and drain the entire reservoir as it is very likely the brake fluid is still there. Use a syringe or a turkey baster to drain the brake fluid from the container. Furthermore, you can disconnect the power steering return line from the pump on the primary side. Remember to disconnect the power steering pump return port that brings back all the fluid you put into another container. When the pump system is empty, you can reconnect the entire system and fill the reservoir with the correct fluid.
After that, turn your car’s steering wheel lock-to-lock two times or more; this will help remove all the air from the system.
In case you cannot flush the power steering fluid yourself, you should immediately contact a trusted mechanic. With their knowledge and the necessary tools, they can help you safely flush and drain your power steering system, change damaged parts if necessary, and add the appropriate fluid.
Can We Use Transmission Fluid for Power Steering?
This is also a common question we want to clarify on this topic. If you ask the manufacturer, they will tell you NO because these two types of oils have completely different functions and should be used for different purposes. But in reality, you can use transmission fluid to replace power steering fluid if necessary. If your car is made by Honda, you absolutely must not use transmission oil to replace power steering oil. The reason is that Honda power steering oil is thicker than ordinary power steering oil and is produced specifically for Honda vehicles.
You should note that using the wrong power steering fluid can lead to leaks, corrosion, damage to internal components, and even complete system failure. It is always best to be cautious and use the exact type of fluid specified for your car.
We hope all this information will be helpful to you in one way or another. The lesson we want to share in this article is that according to each system present in the car, you must choose a suitable fluid recommended by the manufacturer and it should not be used indiscriminately or mixed as they can lead to extremely serious consequences.
If you are unsure or cannot find the above information, a qualified mechanic or dealership representative can look up the exact fluid recommended for your specific car model and year. If you have any concerns, remember to leave your comments in our comment section below.