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Can you substitute power steering fluid with anything?

In general, you should not substitute power steering fluid with other liquids. Use the exact fluid specified by the manufacturer. Some older hydraulic systems tolerate automatic transmission fluid (ATF), but this is not universal, and many newer cars with electric power steering require no hydraulic fluid at all.

Power steering designs vary widely. The key question is whether your car uses hydraulic power steering or an electric system, and what the reservoir cap and manual specify. This article explains what can be used, what to avoid, and how to handle emergencies safely.

Know your system: Hydraulic vs Electric

Most older vehicles rely on a hydraulic power steering system that uses a dedicated fluid or ATF. Newer models increasingly use electric power steering (EPAS), which often does not require any hydraulic fluid. Identifying your system type is the first step in determining whether substitutions are possible.

Key differences to watch out for

Hydraulic power steering systems circulate fluid through a pump, rack and pinion, and hoses; the reservoir label typically reads Power Steering Fluid (PSF) or a manufacturer-specified fluid type.

Electric power steering systems use sensors and an electric motor; they generally do not have a hydraulic reservoir for steering fluid and do not require regular PSF maintenance.

Mixing fluids or using the wrong type can damage seals, reduce performance, or cause pump failure in hydraulic systems; in EPAS, adding fluid is often a non-solution and could mask a fault.

Bottom line: Confirm whether your car is hydraulic or electric and follow the specification in the owner's manual or on the reservoir cap. If you’re unsure, err on the side of professional service.

What you should use and what to avoid

Before listing the guidelines, understand that the manufacturer’s specification is your authoritative source. The following guidance covers typical scenarios, but check your manual for your exact model.

Use the exact fluid specified by the manufacturer. This could be a dedicated Power Steering Fluid (PSF) or a particular ATF type as indicated by the manual or reservoir cap.

Do not mix different fluids unless the manual explicitly allows it; if you must change fluid type, flush the system first to avoid contaminants or incompatible mixtures.

Follow the label on the reservoir cap or the service manual to determine compatibility; some vehicles require PSF, others require ATF (Dexron/Mercon equivalents), and others use EPAS that requires no fluid.

Bottom line: Using the wrong fluid can lead to leaks, swollen seals, reduced steering feel, and pump or rack damage. When in doubt, consult a dealership or qualified mechanic.

Emergency substitution guidelines (pinch scenarios)

If you’re stranded and cannot obtain the recommended fluid, your course of action depends on your vehicle’s design. Some older hydraulic systems tolerate ATF under specific specifications; others do not. This is a high-risk move and should only be considered if the manual explicitly allows it and you understand the risks.

If the manual explicitly allows ATF (with the correct Dexron/Mercon specification) for your hydraulic PS system, you may top up or replace with that ATF type as instructed; avoid mixing with PSF unless the manual says it’s okay.

If there is no guidance permitting ATF, do not substitute; arrange roadside assistance and obtain the correct PSF or have the vehicle towed to a shop.

Do not substitute with brake fluid, engine oil, coolant, or water. These fluids can cause severe seal damage, corrosion, and steering failure.

In practice, avoid improvisation. The long-term cost of damaging a steering system far outweighs the inconvenience of waiting for the correct fluid.

Electric power steering: a special case

Many modern vehicles use electric power steering (EPAS). In these cars, there is typically no hydraulic steering fluid to add or replace. If you see a reservoir, it is usually not for steering fluid or is used for a different purpose. Adding fluid will not restore or improve EPAS performance and could cause damage. When in doubt, consult the owner's manual or a dealer for guidance.

Bottom line: For EPAS-equipped vehicles, there is nothing to substitute; maintenance focuses on electrical components and software rather than fluid changes.

Summary

The correct approach to power steering fluid is to follow the manufacturer’s specification precisely. Most hydraulic systems require PSF or a specific ATF type, which must be verified via the owner’s manual or reservoir cap. Some older hydraulic systems may tolerate ATF, but this is not universal, and many modern cars use electric power steering with no fluid required. Never substitute with brake fluid, engine oil, coolant, or water, and avoid mixing fluids unless explicitly permitted. When in doubt, seek professional service to protect the steering system and safety on the road.

What can be used at power steering fluid?

ATF
ATF is often used as Power Steering Fluid. Recommended for complete fluid replacement or top-off in most passenger cars and light duty trucks.

What can I use for a substitute for power steering fluid?

The best power steering fluid substitute is the fluid recommended in your vehicle's owner's manual; however, if an emergency requires a substitute, automatic transmission fluid (ATF) is the most common and generally safest option for many vehicles, as both are hydraulic fluids. However, never use brake fluid, as it can quickly damage seals and the pump. Some manufacturers specify certain types of ATF, while others have specific synthetic or mineral-based power steering fluids.
This video discusses the differences between automatic transmission fluid and power steering fluid: 1mTalkingTechTrendsYouTube · Apr 5, 2025
When to use a substitute

In an emergency: If you need to add fluid to get to a repair shop, ATF is the most likely substitute to work in a pinch.
When the manual recommends it: Many older cars and trucks are designed to use certain types of ATF for their power steering systems, so always check the owner's manual first.

What to avoid

Never Brake fluid: substitute brake fluid for power steering fluid. It will degrade rubber seals and damage the pump and other components, leading to costly repairs.
Incorrect ATF: Avoid specialty or "performance" ATFs, as these may have different friction modifiers that can negatively affect your power steering system.
Mixing fluids: Avoid mixing fluids of different types if possible. Mixing can lead to a loss of steering assist and other issues.

This video explains why you should not use brake fluid as a substitute for power steering fluid: 43sAutomobile basic ideasYouTube · Jul 15, 2023
Why substitutes can be risky

Damage to components: Mixing or using the wrong fluid can cause damage to the power steering pump, seals, and other parts.
Loss of steering assist: Some substitutes can lead to a noticeable decrease in steering assist or cause the steering wheel to become stiff.
Voided warranty: Using a non-recommended fluid may void the warranty on your power steering components.

Summary of fluid options

Fluid Type	When to use
Owner's Manual Recommended Fluid	Always the first and best option.
Automatic Transmission Fluid (ATF)	Acceptable in an emergency for vehicles where the manual specifies it.
Synthetic Power Steering Fluid	Acceptable if the manual specifies it.
Brake Fluid	Never use as a substitute.

Can you use vegetable oil for power steering fluid?

No, you should not use vegetable oil for power steering fluid because it will damage the system. Power steering fluid is specifically formulated to resist high temperatures, lubricate the pump, and protect against corrosion, while vegetable oil breaks down, thickens in the cold, and can damage seals and clog passages, leading to costly repairs.
Why vegetable oil is a bad substitute

It will degrade: Vegetable oil is not designed to withstand the high temperatures of a power steering system and will break down, which can strain the pump.
It can damage seals: The composition of vegetable oil can cause the seals and other rubber components in the system to degrade and leak over time.
It will clog passages: As the oil breaks down and thickens, it can clog the narrow passages in the power steering system, leading to pump failure.

What to do instead

Use the correct fluid: Always use the power steering fluid recommended by your vehicle's manufacturer.
Use a suitable alternative in an emergency: If you need to top off your fluid in an emergency, a better alternative is automatic transmission fluid (ATF) or, in a pinch, even regular motor oil, though this can still cause issues long-term. However, you should flush the system and refill it with the correct power steering fluid as soon as possible.

What to use to replace power steering fluid?

You're going to need a turkey baster, power steering fluid, a container for waste power steering fluid. And if you have a jack and jack stands, you can use those as well. However, they're optional.

Kevin Bennett

Company Owner

Kevin Bennet is the founder and owner of Kevin's Autos, a leading automotive service provider in Australia. With a deep commitment to customer satisfaction and years of industry expertise, Kevin uses his blog to answer the most common questions posed by his customers. From maintenance tips to troubleshooting advice, Kevin's articles are designed to empower drivers with the knowledge they need to keep their vehicles running smoothly and safely.