Does Power Steering Fluid Evaporate?

Power steering is a vital component in any vehicle, allowing drivers to steer their cars and trucks easily. However, like all fluids in a vehicle, the power steering fluid can go low due to leakage in system. This raises the question: does power steering fluid evaporate, and if so, what are the implications?

In this article, we will see if power steering fluid evaporates, the probable causes of low power steering fluid levels, and how long power steering fluid can last in a car. But first, let’s see what power steering fluid means.

does power steering fluid evaporate

What is Power Steering Fluid?

A power steering fluid is a hydraulic fluid used in the power steering system of a vehicle. The power steering system allows drivers to turn the wheels of their cars and trucks comfortably. Where is the power steering fluid, anyway?

Power steering fluid is stored in a reservoir under the hood of the vehicle and is used to transfer energy from the power steering pump to the steering rack or box. It is also used to lubricate the moving parts of the power steering system, helping to reduce friction and wear.

The fluid is typically red and is specifically formulated for use in power steering systems. However, some may color like engine oils. Using the correct type of power steering fluid as specified by the vehicle manufacturer, as using the wrong type of fluid may cause damage to the power steering system.

Does Power Steering Fluid Evaporate?

Power steering fluid does not evaporate like gasoline. However, many people mistake the issues of bubbles or foams in the power steering reservoir for evaporation. Evaporation is the process by which liquid turns into gas, and the steering fluid does not change from liquid to gas. Instead of evaporation, steering fluid can disappear from the container due to leaks.

Under regular use, power steering fluid should not go low unless there’s a leak in the system, which allows fluid to escape. If you’re repeatedly topping up the fluid, diagnosing and addressing any power steering fluid leak is essential as soon as possible.

Probable causes of power steering fluid loss

The primary cause of power steering fluid loss is leakage in the system. If you are asking why is my power steering fluid low, several factors can be responsible, including:

Leaks in the power steering hose or pump

These can cause steering fluid to leak out, reducing the overall amount of fluid in the system. In extreme cases, a severe leak can cause power steering fluid suddenly empty. Plus, if you think your power steering fluid is low but there’s no leak, you have to check the rack and pinion or the steering box. The leak can come from anywhere in the system.

Worn or damaged seals

Over time, power steering system boot can wear out or become damaged, leading to leaks and fluid loss.

Normal wear and tear

Power steering systems are subject to normal wear and tear; eventually, the system may need to be replaced. Of course, normal wear and tear can lead to system leaks, invariably causing a loss of power steering fluid.


Overheating can cause power steering fluid to boil and drip off the reservoir, leading to a loss of fluid and poor steering performance.

It is essential to check the power steering fluid level regularly and address any leaks or issues as soon as possible to avoid damage to the power steering system. It is best to take your car to a professional mechanic for inspection and repair unless you understand the inner workings of your car.

Does the power steering fluid dry up?

Power steering fluid does not typically “dry up.” The fluid is designed to be a lubricant and is used to help the power steering pump and other components of the power steering system work smoothly and efficiently.

However, the power steering fluid can become contaminated over time, which can cause it to become less effective and may even lead to system failure. Contamination can occur from various sources, including dirt, debris, and other impurities that can find their way into the system.

Also, if a vehicle is not driven frequently, the fluid can become stagnant and lose some of its lubricating properties.

If the fluid container is dry, you have a leak somewhere in the power steering system that needs urgent attention. If this is the case, refilling the container with a fresh fluid will not address the issue. You have to track where the leak is coming from and rectify it.

It’s recommended to check the power steering fluid levels periodically and has it replaced if necessary. And also, have the system checked if there is burnt power steering fluid or any signs of contamination.

How long does a power steering fluid last?

If you’re asking, how long does power steering fluid last? Power steering fluid is designed to last 40,000 to 80,000 miles or after 2 to 3 years. However, it is recommended to check the fluid level periodically and have it replaced if necessary. The lifespan of a power steering fluid can vary depending on factors such as the type of fluid, the driving conditions, and the maintenance of the vehicle.

We suggest to follow the vehicle’s manufacturer’s recommendations for power steering fluid replacement. Some vehicles may recommend replacing the fluid at specific mileage intervals, while others may not have any specific recommendations.

However, suppose the fluid becomes contaminated or dirty. In that case, it will lose its lubricating properties and may cause damage to the power steering system, and it should be replaced as soon as possible.

Is dry steering harmful?

Dry steering fluid, also known as low or no power steering fluid, can cause the power steering system catastrophe. When the power steering fluid level is low, the pump can run dry, which can cause it to become damaged or even seize.

This can lead to a loss of power assist, making it difficult to steer the vehicle. Additionally, running the power steering system without enough fluid can cause damage to the rack and pinion or the steering gear box, and can also cause damage to the seals.

It’s essential to keep an eye on the power steering fluid level and top it off as needed to avoid dry steering and ensure proper lubrication of the power steering components.

How long can you drive without power steering fluid?

It is not recommended to drive a vehicle for an extended period without power steering fluid as it can cause severe damage to the power steering system. Driving without the power steering fluid for more than five minutes will cause catastrophic damage to the power steering system.

The problem will start with a grinding noise before it escalates to significant issues. Therefore, I recommend you check the power steering fluid level regularly and top it off as needed. If you suspect a leakage or low fluid level, it is best to have it checked by a professional as soon as possible.

Final words

This article has cleared the confusion, does power steering fluid evaporate? Power steering fluid does not evaporate, but it can become low or dry due to leakage in the system. To keep your power steering system running smoothly, it’s important to check the fluid level regularly, address any leaks, and change the fluid regularly as per the vehicle manufacturer’s recommended schedule.


Mr. Shafiqule Islam is a graduated Mechanical Engineer and has more than 15 years experience of repairing and maintenance of different brand vehicles like Toyota, Mitsubishi, Ford, Mercedes, BMW etc. He is also giving training to Mechanics. He has started writing to share his practical knowledge to Vehicle Owners, Drivers and Mechanics to keep their cars at best fit.

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