Can I just refill my power steering fluid?

Yes. You can generally top up the power steering fluid yourself if you use the correct type and watch for leaks, but simply adding fluid won’t fix leaks and using the wrong fluid can damage the system.

Know the right fluid for your system

Power steering systems come in hydraulic designs that use a dedicated power steering fluid (PSF) or certain automatic transmission fluids (ATF) as a substitute. Some newer models rely on electric power steering (EPS) and do not have a reservoir for PS fluid. To avoid damage, identify which type your vehicle uses and only refill with the recommended fluid. Check the owner's manual, the reservoir label, or the manufacturer's website. Do not mix different fluids or top up with an incompatible substance, and never reuse old fluid that has contaminated with dirt or water.

Is your system hydraulic or electric?

Most older vehicles and many mainstream models use hydraulic power steering with a distinct reservoir and cap labeled Power Steering Fluid. Some newer models rely on electric power steering (EPS) and have little or no hydraulic fluid reservoir. If you can’t locate a PSF reservoir or the steering feels normal without fluid, you may have EPS. When in doubt, consult the manual or a dealer.

Conclusion: If you confirm you have hydraulic PS, proceed with topping up using the correct PSF. If EPS, there is nothing to fill and attempting to add fluid can damage the system.

Steps to refill and bleed the system

Follow these steps to safely top up and bleed air from a hydraulic power steering system. Gather the right fluid, a clean funnel, rags, and take precautions around hot engine components.

1. Park on a level surface and set the parking brake. Wait until the engine is cool to avoid burns.


2. Open the hood and locate the power steering reservoir. Read the label to confirm the correct fluid specification.


3. Clean the reservoir cap and the area around it before opening to minimize contamination.


4. Check the level with the dipstick or marks on the reservoir; if it’s below the "Full" or "Max" line, plan to top up.


5. With the engine OFF, slowly add the specified PSF until the level reaches the full mark. Do not overfill beyond the maximum line.


6. Replace the cap securely and start the engine. With the engine idling, turn the steering wheel from lock to lock several times to circulate the fluid and expel air.


7. With the engine running, check the level again and add fluid if needed to bring it to the proper level. Do not overfill.


8. Recheck the system after driving for 5–10 minutes of light steering to ensure there are no leaks and the level remains stable.

Conclusion: If the fluid level drops again quickly or you notice bubbles, discoloration, or a whining pump, there may be a leak or a failing pump that warrants professional service.

Common mistakes and warnings

Be aware of pitfalls that can damage the system or mask bigger issues. Here are frequent errors people make when refilling power steering fluid.

• Using the wrong type of fluid. Different cars require different PSF specifications; using ATF or a generic fluid can degrade seals and pumps.


• Overfilling. Excess fluid can build pressure or leak into the engine bay and create messes or damage gaskets.


• Not bleeding the air fully. Air in the system can cause whining, steering feel issues, or noise while turning.


• Ignoring leaks. A rapidly dropping fluid level indicates a leak that needs repair; topping up is a temporary fix at best.


• Driving with a compromised system. Prolonged driving with low PSF can damage the power steering pump and belt drive.

Conclusion: For persistent or advanced issues, consult a trained mechanic to inspect hoses, seals, and the pump, and perform a proper flush if required.

Is your car hydraulic or electric power steering?

As more vehicles adopt electric power steering (EPS), some cars have little to no hydraulic fluid reservoir. Check the manual or look under the hood for a reservoir labeled Power Steering Fluid. If there’s no reservoir or label for PSF, you likely have EPS and there’s nothing to fill. Maintenance steps for EPS differ and may involve software updates or component checks rather than a fluid change.

How to tell

Common indicators your vehicle uses hydraulic PS include a visible reservoir labeled Power Steering Fluid, a pump at the front of the engine, and a clearly labeled cap. If you don’t see a reservoir or the steering feels normal without fluid, you may have EPS. When in doubt, verify with the dealership or service manual.

Conclusion: Correctly identifying your steering system type is essential to avoid unnecessary fluid changes and potential damage.

Summary

You can usually refill power steering fluid yourself if your car has a hydraulic system and you use the correct PSF type. Always check the owner’s manual, avoid mixing fluids, and address leaks rather than just topping up. If you’re unsure or encounter persistent issues—noise, stiffness, or rapid fluid loss—seek professional service. For vehicles with electric power steering, there is typically no reservoir to fill, and maintenance steps differ.

Can you refill your power steering fluid?

If your power steering reservoir is low on fluid, you'll need to add more to help keep your power steering system healthy. Here's how it's done. Get a quart of the correct power steering fluid for your vehicle. Check your owner's manual for more information.

Do you leave the car running when adding power steering fluid?

No, you do not put power steering fluid in while the car is running. It is best to turn the engine off to check the level and add fluid, as the fluid expands when it's hot. While running the engine is necessary to get the fluid to its "hot" operating temperature, the actual process of topping off the reservoir should be done when the engine is off. 
How to correctly add power steering fluid
This video demonstrates how to check and add power steering fluid: 31sYourMechanicYouTube · Jun 1, 2016

• Warm up the engine: Run the car for a few minutes until it reaches normal operating temperature. 
• Turn the engine off: Shut the engine off completely before you open the hood. 
• Locate the reservoir: Find the power steering fluid reservoir, which may have a cap with a steering wheel icon on it. 
• Clean the area: Wipe the reservoir cap and surrounding area with a clean rag to prevent dirt from entering the system. 
• Check the level: Check the fluid level using the dipstick or the "hot" and "cold" lines on the reservoir itself. 
• Add fluid: If needed, add the correct type of power steering fluid to the "hot" line. 
• Important: Do not overfill the reservoir, as the fluid expands when hot and overfilling can cause it to leak. 

What happens if you completely run out of power steering fluid?

If you run out of power steering fluid, you will experience difficulty steering, potentially loud whining noises, and your car's power steering pump will overheat and seize up. The lack of fluid can quickly cause irreversible damage to the pump, hoses, and seals, and a seized pump can break the serpentine belt, which could cause your alternator and water pump to fail as well. 
Immediate effects

• Difficulty steering: Steering will become stiff and hard to turn, especially at low speeds, because the hydraulic pressure is gone. 
• Loud noises: You may hear a whining, groaning, or squealing sound coming from the power steering pump when you turn the wheel. 
• Jerky steering: The steering might feel jerky or jumpy instead of smooth. 

Long-term damage

• Pump damage: The pump will overheat and seize due to increased friction from running without lubrication. This is a very common and expensive repair. 
• Serpentine belt failure: If the pump seizes, it can cause the serpentine belt to snap, which will disable your alternator (no charging the battery) and often the water pump (engine cooling). 
• Hose and seal damage: The lack of fluid flow and high heat can cause the hoses and seals to age prematurely and become damaged, leading to more leaks. 
• Steering rack damage: The steering rack itself can be damaged from running without fluid. 

What to do

• If you notice any signs of low power steering fluid, stop driving the vehicle as soon as it is safe to do so. 
• Check the fluid reservoir and add the correct type of power steering fluid if it is low, being careful not to overfill. 
• If the fluid was completely empty or you see fluid leaking under your car, it is crucial to have the system inspected by a mechanic to address the cause of the leak and any potential damage. 

Can you mix old power steering fluid with new?

Yes, you can add new power steering fluid to old fluid, but it's best to replace it entirely to avoid potential issues. Adding new fluid can be a temporary solution, but mixing old and new fluids can lead to decreased steering performance or premature wear over time. 
Why replacing is better

• Degraded performance: Old fluid can become contaminated with moisture and wear particles, and its lubrication properties can degrade. Mixing can lead to decreased efficiency.
• Component wear: Incompatible fluids can cause premature wear on components like the pump and seals.
• Fluid types matter: Not all power steering fluids are interchangeable. Mixing different types could cause chemical reactions, such as turning the fluid into a jelly-like substance.
• Potential leaks: Different fluids can damage seals, leading to leaks. 

How to add new fluid temporarily

• Check your owner's manual: First, identify the correct type of power steering fluid for your vehicle. Using the wrong type is a common cause of pump failure. 
• Siphon out old fluid: Use a turkey baster or siphon to remove as much of the old, dark fluid as you can from the reservoir. 
• Add new fluid: Fill the reservoir with the new, correct fluid, but do not overfill. 
• Circulate and repeat: Start the engine and turn the steering wheel from lock to lock several times to mix the new fluid with any remaining old fluid. Then, repeat the siphoning and refilling process until the fluid being pumped out is close to the color of the new fluid. 

This video demonstrates how to replace power steering fluid: 1mYour Home GarageYouTube · Jun 26, 2023