Why Is My Power Steering Fluid Foamy

Why is my power steering fluid foamy? If you are faced with this problem, read on to know the reasons and what you can do to solve the problem.

Almost every modern automobile uses power steering. If the vehicle you drive uses a power steering fluid, you should keep an eye on the appearance of the fluid. Have you ever noticed how the fluid can get foamy? If this happens often, then this article is for you. 


Why Is My Power Steering Fluid Foamy

What Would Cause the Power Steering Fluid to Foam Up?

The power steering fluid in the reservoir may appear foamy at times. You will notice small air bubbles filling up the reservoir, making the fluid appear frothy and foamy. When the fluid appears foamy, the steering will become heavy, and you will also hear a loud noise from the power steering pump. 

The fluid foams up when air rushes into the system. But how does the air enter the system? 

Improper Drainage

Usually, it happens due to improper drainage. 

The reservoir needs to be drained from time to time and then filled with new fluid. If you cannot drain it correctly, the reservoir will trap air, and the fluid will foam up. When it foams up, you will need to bleed the power steering to get rid of the air bubbles. 

Entry Of Air

Sometimes, air enters the reservoir even when you have drained it properly. When you’ve allowed the system to drain correctly and then filled it up, there are only three places air can enter through:

  1. The front seal on the power steering pump
  2. Pipes between the power steering pump and the fluid reservoir
  3. Low-pressure connection on the power steering pump

The impeller of the power steering pump whips the air when it enters through these channels. Due to the whipping of the impeller, the fluid becomes foamy and bubbly. Such foamy fluid cannot function properly and is unable to regulate the system. Due to this, the steering becomes very heavy. 


Why Is My Power Steering Fluid Foamy

Power Steering Fluid Color

The color of the power steering fluid depends on the chemical composition of the fluid. When the fluid becomes foamy, it does not change color. If air enters, the only indication is the foam. Keep an eye out for frothy fluid as it will affect the steering even before the fluid changes color and needs to be flushed out. 

Why Is My Power Steering Fluid Brown and Foamy?

Power steering fluid changes color after a while. The fluid’s original red, pink or clear tone may eventually turn brown or black. It will happen if you do not drain the reservoir and refill it when necessary. The fluid is in contact with the rubber seals of the power steering pump. Contaminants and air will enter the fluid if the seals are broken, turning it brown and foamy. 

If the fluid reservoir has not been drained and refilled with new fluid for a long time, the color of the power steering fluid can turn a dark brown. 

It is quite natural for the original color of the fluid to darken and become murky amber or brown. However, if the fluid is also foamy, that is a sign of air entering the system. The air can only enter through a broken or worn-out rubber seal. 

If the front rubber seal of the steering fluid pump is not working, contact with the fluid will cause contamination. Air will continue to enter the fluid, and there will be leakage. You should check your vehicle, particularly underneath your car, and see if the power steering fluid is leaking. 

Suppose you notice that the power steering fluid is brown in color and foamy. Check the front seal of the pump immediately. Drain the brown fluid, repair or replace the seal and refill the reservoir with new fluid. 

Don’t wait for too long to get the system serviced. If you leave the foamy, brown fluid in the reservoir for too long, the steering will become very heavy, and it will be challenging to drive. 


Why Is My Power Steering Fluid Foamy

How Do I Stop My Power Steering Fluid From Foaming?

The only way to stop the power steering fluid from foaming is to ensure that air cannot enter through any part of the system. While the pump and the seals might malfunction, allowing air to get sucked into the reservoir, there might also be problems with the pipework. So before you get the pump replaced, ask a mechanic to check the pipes thoroughly. 

Stiff Rubber Hose

There is a rubber hose between the pump inlet and the fluid reservoir. The hose should not be too hard. If it is stiff, it might become brittle, or cracks will appear. You should also check the clamps. If the clamps are tight, they will create an airtight seal. The seal will prevent air from entering, and the power steering fluid will not foam up. 

Damaged O-Ring

Apart from the front rubber seals of the power steering fluid, certain vehicles also have an O-ring that seals the low-pressure connection to the pump. Air rushes into the system and the fluid if the O-ring is damaged. 

Like the rubber hose, the O-ring too can become hard and crack. If it breaks, then it will be tough to prevent air bubbles. The fluid will foam up. Therefore, you should have these parts appropriately inspected before deciding on repairs or replacements. 

Pump Damage

If you find no issues with the pipes or the O-ring, then the problem lies with the pump. Check the seals of the pump and have them replaced before bleeding the power steering system. 


Why Is My Power Steering Fluid Foamy

How Long Does It Take To Get Air Out of Power Steering?

You will need to bleed the power steering system to get the air out. When you notice the foamy, frothy fluid, let your vehicle stand for an hour. Make sure the engine is not running. It will make the bleeding process much more manageable. Then continue with the bleeding to expel the air. To bleed the system, you will have to turn the steering wheel lock constantly. If you do it a few times, you will expel the air, and the fluid will no longer appear foamy. It does not take more than 10 minutes to bleed the system and get the air out. 

Wrap Up

To ensure smooth steering, you must maintain the power steering fluid and the entire system. You can maintain the power steering system better now that you know why the fluid foams up and how to deal with it. Don’t forget to share this article with automobile enthusiasts and leave a comment below if you’ve enjoyed this article. 

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Sean Mendez

Hi, I am Sean, a self-confessed petrolhead. I live in Boise, Idaho with a busy family of four and our energetic Labrador retriever. Thank you for visiting my website. You can find my email on the contact page.

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