What happens if I put the wrong steering fluid in my car?
Using the wrong steering fluid can damage the power steering system, leading to stiff or noisy steering, leaks, and potentially pump or seal failure. The remedy is to stop using the wrong fluid, drain and flush, and refill with the correct specification per your owner's manual.
Why steering fluid type matters
Your vehicle’s power steering system relies on the right hydraulic fluid to lubricate seals, cushions, and the pump. Different systems are designed for specific fluid formulations, and using the wrong one can compromise performance and longevity.
- Some vehicles require conventional power steering fluid specified by the manufacturer.
- Other models have used automatic transmission fluid (ATF) in the past; this is still common in older vehicles.
- More newer vehicles need a dedicated power steering fluid or a synthetic product with a specific viscosity and additives.
- Mixing fluids or using engine oil, brake fluid, or other substitutes can cause chemical reactions, foaming, or seal damage.
Using the wrong fluid isn't always immediately catastrophic, but it can lead to accelerated wear and unexpected failures if left unchecked. If you recently added an improper fluid, the safest course is to have the system inspected by a professional.
What can go wrong: symptoms to watch for
The most common issues arise from incompatible seals, lubricants, and additives. Here are typical signs a wrong fluid has entered the system:
- Whining, groaning, or squealing noises from the steering pump
- Stiff, hard, or delayed steering response
- Foaming or milky-looking fluid in the reservoir
- Leaking hoses or damp spots around the pump or rack
- Rapid drop in fluid level without obvious leaks, indicating internal damage
- In extreme cases, loss of hydraulic assist and difficulty steering
If you notice any of these symptoms, stop driving if safe to do so and seek professional evaluation. Prompt action can prevent further damage.
What to do if you’ve already added the wrong fluid
Take immediate steps to minimize damage and restore the system to its intended specification.
- Do not drive the car aggressively or for long distances; limit operation to nearby, safe routes if you must move it.
- Check your owner’s manual or the reservoir cap for the exact recommended fluid type and viscosity.
- Avoid adding more fluid of any type until the system is inspected if you’re unsure about the current fluid.
- Have the system drained, flushed, and refilled with the correct fluid by a qualified technician. Some vehicles require a full system flush; others may be serviced by a reservoir drain and refill.
- Inspect for leaks, damaged hoses, or swollen seals and replace worn components as needed.
- After service, verify the level and operation by a careful test drive in a safe area and monitor for leaks.
Timely servicing is key to avoiding costly pump or rack replacement. A professional will ensure the right specification is used and that any damaged seals are replaced.
Prevention: tips to avoid the mistake in the future
Simple habits can help ensure you always use the correct fluid for your vehicle’s steering system.
- Refer to the owner’s manual or the cap on the reservoir for the exact fluid specification.
- Label and store the steering fluid you use in your garage; never refill with a different type without confirming compatibility.
- Use a dedicated funnel and container to avoid cross-contamination with other fluids (like ATF or engine oil).
- When in doubt, have a professional perform the refill or fluid change rather than doing it yourself.
Keeping to the manufacturer’s specification helps protect seals, reduces noise, and preserves steering performance over time.
Summary
Putting the wrong steering fluid into a car can cause a range of problems from minor annoyances to serious mechanical damage. The core risk is that incompatible fluids can degrade seals, cause foaming, and stress the steering pump. If you suspect the wrong fluid has been used, minimize driving, consult the manual, and seek professional service to drain, flush, and refill with the correct fluid. Prevention boils down to using the exact fluid specified by the manufacturer and preventing cross-contamination in the reservoir.
Does it matter what power steering fluid you put in?
Yes, it is critical to use the correct power steering fluid, as using the wrong type can cause significant damage to the system, including the pump and seals. The correct fluid specification can be found in your vehicle's owner's manual, and is essential for proper steering performance and longevity.
Why the correct fluid is important
- Prevents damage: Power steering systems have very specific requirements. Using the wrong fluid can cause seals to swell or other components to fail, leading to leaks and a shortened lifespan for the system.
- Maintains performance: The correct fluid ensures consistent and smooth power assistance. The wrong fluid can lead to poor steering performance, making the wheel feel stiff or inconsistent.
- Avoids noise: An incorrect fluid can cause the pump to make whining noises, which is a sign of a system under stress.
How to find the right fluid
- Check your owner's manual: This is the most reliable source for the specific type of fluid your vehicle needs.
- Look for labels: The correct specification is often printed on the power steering fluid reservoir cap.
- Consult service information: If the information isn't on the cap or in the manual, a service technician can look it up in the vehicle's service information.
- Consider your vehicle's age: Some manufacturers used specific types of fluid (like certain automatic transmission fluids) in older vehicles, while most newer cars require a dedicated synthetic power steering fluid.
What happens if you put the wrong power steering fluid in your car?
Putting the wrong power steering fluid in your car can damage the pump, rack, and seals, leading to poor steering performance, noise, and leaks. It's essential to use the specific fluid recommended in your vehicle's owner's manual or on the reservoir cap to prevent premature wear and costly repairs.
What can happen
- Component damage: Incompatible fluids can cause friction and wear on power steering components like the pump and rack.
- Seal and hose damage: The wrong fluid can chemically react with and degrade rubber seals and hoses, leading to leaks.
- Performance issues: You may experience inconsistent power assist, a changed feel in the steering, or loud noises from the system.
- Overheating: The system can overheat, which can cause further damage to the pump.
- Pump failure: In some cases, the pump can fail completely, and it's possible for failure to occur after only a short period of use.
What to do if you've used the wrong fluid
- Stop driving the car: If you've just put the wrong fluid in, avoid driving the car to prevent further damage.
- Do not start the engine: If you know you've used the wrong type, avoid starting the engine to prevent the pump from running with the incorrect fluid.
- Have the system flushed: The correct action is to have the entire system professionally flushed and refilled with the proper fluid.
- Check the manual: Always check your owner's manual or the reservoir cap for the exact type of power steering fluid your vehicle requires.
Is it okay to mix different power steering fluids?
No, you should not mix different types of power steering fluids, such as mineral-based and synthetic, as this can degrade additives, decrease performance, and cause system damage. Mixing fluids is generally not recommended unless they are the same type and meet the same specifications. Always consult your vehicle's manual for the correct fluid type to use and avoid mixing different fluids unless it's an emergency.
Why you shouldn't mix power steering fluid
- Incompatible formulas: Power steering fluids are not all the same; mineral-based and synthetic fluids have different chemical properties that can cause issues when mixed.
- Reduced performance: Mixing can reduce the fluid's ability to lubricate and protect components, leading to a decrease in steering efficiency.
- Component damage: Incompatible fluids can cause premature wear on parts and damage seals, potentially leading to leaks over time.
- Gel-like buildup: Some fluid combinations can turn into a jelly-like substance, clogging hydraulic lines and causing significant problems.
What to do instead
- Check your manual: The most important step is to check your vehicle's owner's manual for the specific type and brand of power steering fluid it requires.
- Stick to one type: If you need to top off your fluid, use the same type and brand that is already in the system.
- Perform a flush: If you've mixed fluids or used the wrong type, the safest option is to completely flush the system and refill it with the correct fluid.
- Consider a professional: If you are unsure about the correct fluid or how to perform a flush, it's best to have a qualified mechanic handle the service.
How to take out extra power steering fluid?
Turn the ignition key to unlock the steering wheel (but do not start the engine), then rotate the wheel slowly lock to lock a few times to push the old fluid out of the system. When done, the reservoir should be completely empty and no additional fluid should drain from the fitting.
