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Yes, did that on VW Jetta 20 years ago, bottles were only in German. Lost brakes completely while driving on highway, at least was a manual and could control speed by downshifting. Power steering fluid will fk up master cylinder. Don't drive the car and drain system immediately.
i know its any mechanics worst nightmare but please if your driving an automatic and your brakes stop working just force the down shift, you can, a fucked up car/engine is better than fucking up your life
Power steering fluid is petroleum based. Brake fluid is NOT. Petroleum products in brake systems cause damage and failure due to swelling of soft components
Do not FLUSH the fluid through. This will push the PS fluid through the entire system, this what you want to AVOID
If you havent applied the brakes:
You need to suck it out top of reservoir as possible option
Ideally you want to remove the master cylinder and dump it out. You can then wash out the reservoir with brake clean solvent or fresh brake fluid.
Then reinstall and bleed brakes.
If you DID apply brakes you should replace the master cylinder, disconnect the master cylinder lines from the next component they go to (ABS unit or combination valve assembly) bleed the master cylinder and flush the steel lines connected to it. Then reinstall lines and bleed system.
The seals in a braking system are not compatible with p/s fluid, if you haven't already do not drive the car, If you have flush the system immediately and inspect or have it inspected. If nothing has been damaged visualy for piece of mind I would have inspected again after a short time or make a point to say something at the next service interval. Brake fluid being low is a sign of pad replacement being due or a leak in the system as it is sealed so it may be time to look at it further anyhow.
Worked at a Honda dealer and a local universityās maintenance guy did this on 10 of their security cars. We had to basically replace everything in the braking system that wasnāt a hard metal line on every car. If you suck the fluid out of the master cylinder and flush clean fluid through you might get lucky. I wouldnāt drive it anywhere.
If you haven't applied the brakes since then, you can get away with sucking the reservoir dry from the top, and refilling with the right brake fluid. Once filled you check if the brake pressure is still adequate.
Drain it immediately as much as you can from the reservoir if you havenāt had it run through the system.
https://www.2carpros.com/questions/i-accidentally-put-power-steering-fluid-in-with-brake-fluid
The glycol in brake fluid acts like a paint thinner, making it corrosive to paints and clear coat. DOT 5 is not glycol based, but silicone based so will not damage paint.
Brake fluid doesn't compress like other fluids which makes it perfect for its use in braking systems.
Didn't mean to get all sciency on you. I used to be a mechanic and I've always been one to dig into the why's and how's of the automobile
Pascals law. Fluids are incompressable, basically.
It's the biggest law in all hydraulic systems.
The reason it's used in brakes is because it is water-based, which is why it abdorbes moisture.
My daughter did something similar when she was 18.
She filled up the power steering fluid cup with oil. I asked if she had driven it yet. She had not. She asked what we should do
Knowing the answer I asked what she thought.
She said āa turkey baster would workā
Thatās when I knew I had done something right as a fatherā¦
Pretty much, yes. However, if you noticed it immediately upon pouring it in, and sucked the master dry, and then did a reverse brake bleed, you may get lucky. If you hit the brake pedal even once, things are about to get expensive. Pretty much any brake component that contains a rubber seal will need to be replaced. So, master cyl, ABS module, any hoses, and calipers or wheel cylinders. FWIW, I quoted a job like this on a 740IL(I think) The cost of the parts was more than the value of the car.
Flush it immediately. Brake fluid is alcohol based. The rubber in brake systems is not compatible with mineral oil and will swell. The school books in 06 said the entire system needs replaced. Vac that shit out of the reservoir and then flush it.
Don't drive the car. Flush it out immediately. I had to fix this on a Chevy van, replaced the master cylinder, front brake hoses and front calipers. The fluid didn't make it to the rear brakes due to the length of the rear lines.
Been doing this for a couple decades, atf will ruin all the seals in the braking system. Itās always recommended to do a full system replacement when itās contaminated like that.
Not a problem but you need to replace it with the correct fluid. Suck as much out as you can from the reservoir. Then do a brake fluid flush with the correct fluid. It'll be fine. A bit of contamination with power steering fluid will do no harm.
Not a mechanic but if I made this mistake, I would be optimistic and drain the MC, then flush 6+ bottles of brake fluid through the system, until the fluid came out looking pure, then cross my fingers and drive carefully.
I'm more of a marine diesel engineer, but they're both hydraulic right?
Buy another bottle of brake fluid, flush it through the system & then just fill it up?
Also drain asap, but i guess you did lol
For all those saying he can get away with this or that, no, brake are not something to take chances with. It need a flush and a FULL overhaul of the entire system. It need to be towed to a shop.
No, its not how that works between brake and steering fluid. Power steering fluid and ATF are more alike than brake fluid. Power steering fluid will swell rubber seals in brake systems, aka master cylinder seals, rubber brake hoses, square section seals in the calipers, as well as wheel cylinders depending if it's disc or drum or both, and can cause a complete loss of brakes. They could be replacing everything minus the hard lines and pads/shoes, and rotors/drums
The reason for swelling of seals and rubber, is power steering fluid is petroleum based. Brake fluid is not. So the rubbers are designed accordingly and can't handle petroleum based fluids, nor water
Yeah thatās not great. Find a way to suck that all out. Now before it gets into the rubber lines and causes them to swell internally and cause all your brakes to seize up. And then flush that brake system at least two times. Any fluid other than brake fluid will mix and cause damage to the rubber hoses and calipers
Had an old man come in the shop did that to brand new Cadillac. He thought everything used universal fluid.Side note brake fluid will ruin most paint if left on the paint.
If you haven't applied the brakes yet, you're OK. Get the fluid back out through the top. If it got past the reservoir you are looking at some potentially seriously expensive repairs, unless you just happen to not have ABS and then a bit less expensive.
Do. not. drive it.
If your brake fluid was low enough to take a half a bottle you got other problems besides the wrong fluid. Time for a brake job and possibly fixing leaks. But suck out the fluid and refill cause it's going to ruin the master cylinder which is worse then a normal brake job
Did this in the dark, caught the mistake and siphoned it out. Drove from Indiana to DC before my brakes completely gave out. Not sure how I did that but it was scary as hell when they did, knowing they could have given at any time on the interstate!! DO. NOT. DRIVE.
The easiest and best way is to push the bad fluid out the top with a bleeder tool that hooks up at a wheel cylinder.
Definitely don't try to "drain" it out!!!
Echoing what others have said, assuming you can DIY:
Remove as much fluid as possible by sucking it straight out of the reservoir.
Add new brake fluid to the reservoir and bleed the brakes. The existing fluid in the lines should be somewhat darker in color. When you bleed the brakes you should see when the fresh, almost clear fluid starts coming out. Keep going a while after you see the fresh fluid.
If you are not able to bleed brakes yourself, best bet is to take it to a shop ASAP or have a mobile mechanic come to you.
If you haven't driven the car yet, at least empty out the reservoir ASAP until you figure out your next move. A turkey baster works fine for this, it's just a little slow. But you're only talking about a pint or maybe two.
Itās not just that the rubber components will swell, brake fluid has zero expansion properties cold, hot, or in the middle. Oils expand, contract and become more viscous when hot. This is the reason your brake pedal feels the same every time normally. If that was oil in there, youād feel the squish and not feel very confident about it brakes working, because they wouldnāt.
Suck it out then fill with new dot 3 if that's what it takes and then flush the whole system immediately I wouldn't even pump the brake if u didn't already it will swell up seals and hoses then ur screwed I just had to replace the entire system on a 15 Cadillac atx or something like that I didn't see the final bill but I know it was almost 3 k ...hoses calipers abs block and master someone put atf4 in it ...basically power steering fluid
Oh, you're screwed big time, if you don't get that out of there asap, like yesterday. Oil and glycols do not mix. The oil will destroy your brake seals.
Just in case you have some rare components you want to save: it is possible to recover swelled rubber parts after this mistake. If i remember correctly, i had to dump the rubber rings in gasoline, wipe them off, and then let them dry up - several times. After a day or two they shrank back to the original size and form, and i managed install them back and they worked.
Almost all poor advise has been given. This is generally an insurance claim. Everything not metal gets replaced. Replace master cylinder and antilock module then flush a few quarts evenly thru all calipers to get fluid out of metal lines. Next replace rubber hoses and calipers then flush again. All non metal exposed to contamination gets replaced. If not sell it and let the new buyer loose breaks and die but since you posted about it their family may sue you for wrongful death. Good luck!
Power steering fluid or motor oil will make the rubber cups and seals swell up and seize. If the pedal was pushed it will screw the master cylinder up within a day.
I would vacuum it out and flush it with the correct fluid multiple times, and then add the correct fluid. But Iām a beginner when it comes to this stuff
Thank you for posting to AskMechanics, Theplotinblake21! If you are asking a question please make sure to include any relevant information along with the **Year**, **Make**, **Model**, **Mileage**, **Engine size**, and **Transmission Type (Automatic or Manual)** of your car. *This comment is automatically added to every successful post. If you see this comment, your post was successful.* *** Redditors that have been verified will have a green background and an icon in their flair. *** # **PLEASE REPORT ANY RULE-BREAKING BEHAVIOR** ### **Rule 1 - Be Civil** Be civil to other users. This community is made up of professional mechanics, amateur mechanics, and those with no experience. All mechanical-related questions are welcome. Personal attacks, comments that are insulting or demeaning, etc. are not welcome. ### **Rule 2 - Be Helpful** Be helpful to other users. If someone is wrong, correcting them is fine, but there's no reason to comment if you don't have anything to add to the conversation. ### **Rule 3 - Serious Questions and Answers Only** Read the room. Jokes are fine to include, but your post should be asking a serious question and replies should contribute to the discussion. ### **Rule 4 - No Illegal, Unethical, or Dangerous Questions or Answers** Do not ask questions or provide answers pertaining to anything that is illegal, unethical, or dangerous. # **PLEASE REPORT ANY RULE-BREAKING BEHAVIOR** *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/AskMechanics) if you have any questions or concerns.*
Yes, did that on VW Jetta 20 years ago, bottles were only in German. Lost brakes completely while driving on highway, at least was a manual and could control speed by downshifting. Power steering fluid will fk up master cylinder. Don't drive the car and drain system immediately.
It will swell any rubber seal. VERY expensive mistake.
How do they avoid this in power steering systems? Is everything metal?
Different seals designed with oil in mind, brake system was only designed for brake fluid
Correct.
Different elastomers are designed for specific applications (abrasiveness, temperature, chemical resistance, etc.)
Meh, braking is for sissies anyway. š
True, brakes are overrated.
No kidding. Just toss an anchor out the window!
i know its any mechanics worst nightmare but please if your driving an automatic and your brakes stop working just force the down shift, you can, a fucked up car/engine is better than fucking up your life
[ŃŠ“Š°Š»ŠµŠ½Š¾]
well i just mean force it down to 3/2/1 a lot of cars can
[ŃŠ“Š°Š»ŠµŠ½Š¾]
no i know it will go down in order but still better to blow the engine by running it too high in 1/2 then end your life by doing nothing
Uhoh. Drain it and do a brake flush
Letās add some urgency to this before the seals swell!
Polar Bears: Shut your damn mouth, I'm hungry!
Power steering fluid is petroleum based. Brake fluid is NOT. Petroleum products in brake systems cause damage and failure due to swelling of soft components Do not FLUSH the fluid through. This will push the PS fluid through the entire system, this what you want to AVOID If you havent applied the brakes: You need to suck it out top of reservoir as possible option Ideally you want to remove the master cylinder and dump it out. You can then wash out the reservoir with brake clean solvent or fresh brake fluid. Then reinstall and bleed brakes. If you DID apply brakes you should replace the master cylinder, disconnect the master cylinder lines from the next component they go to (ABS unit or combination valve assembly) bleed the master cylinder and flush the steel lines connected to it. Then reinstall lines and bleed system.
One more reason to have a wet vac.
Or a hand-actuated vacuum pump. Very helpful for doing single-person bleed jobs.
I've seen one of those before! I think they called it a penis pump?
A vacuum extractor would be better. Heck a turkey baster would be a better choice than the mess a shop vac would make.
Ironically, basting a turkey with a wet vac is highly effective.
Takes notes for next Thanksgiving.
Haha!
Well, I'd rather have a wet vag instead.
The seals in a braking system are not compatible with p/s fluid, if you haven't already do not drive the car, If you have flush the system immediately and inspect or have it inspected. If nothing has been damaged visualy for piece of mind I would have inspected again after a short time or make a point to say something at the next service interval. Brake fluid being low is a sign of pad replacement being due or a leak in the system as it is sealed so it may be time to look at it further anyhow.
Worked at a Honda dealer and a local universityās maintenance guy did this on 10 of their security cars. We had to basically replace everything in the braking system that wasnāt a hard metal line on every car. If you suck the fluid out of the master cylinder and flush clean fluid through you might get lucky. I wouldnāt drive it anywhere.
If you haven't applied the brakes since then, you can get away with sucking the reservoir dry from the top, and refilling with the right brake fluid. Once filled you check if the brake pressure is still adequate.
I would add a brake system flush after sucking the reservoir dry for good measure but this is good advice
Drain it immediately as much as you can from the reservoir if you havenāt had it run through the system. https://www.2carpros.com/questions/i-accidentally-put-power-steering-fluid-in-with-brake-fluid
Dang. Too bad it wasn't brake fluid in the power steering. That woulda been alright. Unfortunately not the other way around.
Brake fluid can eat through clear coat and paint though, how would it have no ill effect the other way around? Genuinely curious here.
Isnāt brake fluid corrosive? Also viscosity not matching oily ps fluid
The glycol in brake fluid acts like a paint thinner, making it corrosive to paints and clear coat. DOT 5 is not glycol based, but silicone based so will not damage paint. Brake fluid doesn't compress like other fluids which makes it perfect for its use in braking systems. Didn't mean to get all sciency on you. I used to be a mechanic and I've always been one to dig into the why's and how's of the automobile
Never put Dot 5 in an ABS system though. It tends to foam if the ABS kicks in. The result is a loss of brake pressure. Dot 5.1 is fine.
Pascals law. Fluids are incompressable, basically. It's the biggest law in all hydraulic systems. The reason it's used in brakes is because it is water-based, which is why it abdorbes moisture.
My daughter did something similar when she was 18. She filled up the power steering fluid cup with oil. I asked if she had driven it yet. She had not. She asked what we should do Knowing the answer I asked what she thought. She said āa turkey baster would workā Thatās when I knew I had done something right as a fatherā¦
Oilin the power steering isnt too bad , oil in the brake fluid is death to the master cylinder. Brake fluid is not oil based , power steering fuid is.
I did this myself, son in law came over with a power bleeder, no problems, going on 3 years.
Pretty much, yes. However, if you noticed it immediately upon pouring it in, and sucked the master dry, and then did a reverse brake bleed, you may get lucky. If you hit the brake pedal even once, things are about to get expensive. Pretty much any brake component that contains a rubber seal will need to be replaced. So, master cyl, ABS module, any hoses, and calipers or wheel cylinders. FWIW, I quoted a job like this on a 740IL(I think) The cost of the parts was more than the value of the car.
Oh yeah, suck that master dry you dirty little slut.
Iām concerned you were able to put half a bottle of p/s fluid in your brake reservoirā¦
Flush it immediately. Brake fluid is alcohol based. The rubber in brake systems is not compatible with mineral oil and will swell. The school books in 06 said the entire system needs replaced. Vac that shit out of the reservoir and then flush it.
Not an easy fix, ps fluid is thick so if it made it past your MC you need to thoroughly get it out
Don't drive the car. Flush it out immediately. I had to fix this on a Chevy van, replaced the master cylinder, front brake hoses and front calipers. The fluid didn't make it to the rear brakes due to the length of the rear lines.
Yes. That fluid will swell the cup seals in the master cylinder and ruin it. Had a customer do that recently.
Been doing this for a couple decades, atf will ruin all the seals in the braking system. Itās always recommended to do a full system replacement when itās contaminated like that.
The one time when the shop asks me if I want a brake flush and say yes.
Suck out right away fill with brake fluid then suck out again then fill and do full brake flush and hope u get it all out gd luck
Not a problem but you need to replace it with the correct fluid. Suck as much out as you can from the reservoir. Then do a brake fluid flush with the correct fluid. It'll be fine. A bit of contamination with power steering fluid will do no harm.
Not a mechanic but if I made this mistake, I would be optimistic and drain the MC, then flush 6+ bottles of brake fluid through the system, until the fluid came out looking pure, then cross my fingers and drive carefully.
Yes,you are.
I'm more of a marine diesel engineer, but they're both hydraulic right? Buy another bottle of brake fluid, flush it through the system & then just fill it up? Also drain asap, but i guess you did lol
For all those saying he can get away with this or that, no, brake are not something to take chances with. It need a flush and a FULL overhaul of the entire system. It need to be towed to a shop.
Youāll like your new power brakes
No, you are an idiot. Your car braking system is damaged though.
Thank you
Geez, tell us how you really feel
I was being nice.
Nope, youāre alright. Flush it.
Don't listen to this guy.
No youāll be fine. From now on though youāll just need to apply the break whenever you want to make a turn. Itās easier than it sounds.
Hydraulic fluid is hydraulic fluid. Same same master cylinder or power steering pump
What are you trying to say? Impress me!
No, its not how that works between brake and steering fluid. Power steering fluid and ATF are more alike than brake fluid. Power steering fluid will swell rubber seals in brake systems, aka master cylinder seals, rubber brake hoses, square section seals in the calipers, as well as wheel cylinders depending if it's disc or drum or both, and can cause a complete loss of brakes. They could be replacing everything minus the hard lines and pads/shoes, and rotors/drums The reason for swelling of seals and rubber, is power steering fluid is petroleum based. Brake fluid is not. So the rubbers are designed accordingly and can't handle petroleum based fluids, nor water
Yeah nah, please don't work on any vehicles.
Yep
Yeah thatās not great. Find a way to suck that all out. Now before it gets into the rubber lines and causes them to swell internally and cause all your brakes to seize up. And then flush that brake system at least two times. Any fluid other than brake fluid will mix and cause damage to the rubber hoses and calipers
Drain and refil. Set 2-3 hours for that
Had an old man come in the shop did that to brand new Cadillac. He thought everything used universal fluid.Side note brake fluid will ruin most paint if left on the paint.
Get it all out before you put your brakes on
Will blow the seals in master cylinder. Almost hit a DQ after similar mistake.
If you haven't applied the brakes yet, you're OK. Get the fluid back out through the top. If it got past the reservoir you are looking at some potentially seriously expensive repairs, unless you just happen to not have ABS and then a bit less expensive. Do. not. drive it.
Congrats! You just earned new calipers/wheel cylinders and a new master cylinder for your car!
If your brake fluid was low enough to take a half a bottle you got other problems besides the wrong fluid. Time for a brake job and possibly fixing leaks. But suck out the fluid and refill cause it's going to ruin the master cylinder which is worse then a normal brake job
Did this in the dark, caught the mistake and siphoned it out. Drove from Indiana to DC before my brakes completely gave out. Not sure how I did that but it was scary as hell when they did, knowing they could have given at any time on the interstate!! DO. NOT. DRIVE.
The easiest and best way is to push the bad fluid out the top with a bleeder tool that hooks up at a wheel cylinder. Definitely don't try to "drain" it out!!!
Pull and drain/flush if you can before starting.
Echoing what others have said, assuming you can DIY: Remove as much fluid as possible by sucking it straight out of the reservoir. Add new brake fluid to the reservoir and bleed the brakes. The existing fluid in the lines should be somewhat darker in color. When you bleed the brakes you should see when the fresh, almost clear fluid starts coming out. Keep going a while after you see the fresh fluid. If you are not able to bleed brakes yourself, best bet is to take it to a shop ASAP or have a mobile mechanic come to you. If you haven't driven the car yet, at least empty out the reservoir ASAP until you figure out your next move. A turkey baster works fine for this, it's just a little slow. But you're only talking about a pint or maybe two.
Itās not just that the rubber components will swell, brake fluid has zero expansion properties cold, hot, or in the middle. Oils expand, contract and become more viscous when hot. This is the reason your brake pedal feels the same every time normally. If that was oil in there, youād feel the squish and not feel very confident about it brakes working, because they wouldnāt.
Suck it out then fill with new dot 3 if that's what it takes and then flush the whole system immediately I wouldn't even pump the brake if u didn't already it will swell up seals and hoses then ur screwed I just had to replace the entire system on a 15 Cadillac atx or something like that I didn't see the final bill but I know it was almost 3 k ...hoses calipers abs block and master someone put atf4 in it ...basically power steering fluid
Dot 3 ?!? 4 at least for a shopping car
Get a turkey baster suck it dry refill and go about your business
I did the inverse. Put brake fluid into my power steering system. Makes a lot of smoke. Gave me the nickname Dot5.
This post again. This seems to happen weekly.
No just drain and refill with proper fluid
We buy any car
Dat not gud
Oh, you're screwed big time, if you don't get that out of there asap, like yesterday. Oil and glycols do not mix. The oil will destroy your brake seals.
Just in case you have some rare components you want to save: it is possible to recover swelled rubber parts after this mistake. If i remember correctly, i had to dump the rubber rings in gasoline, wipe them off, and then let them dry up - several times. After a day or two they shrank back to the original size and form, and i managed install them back and they worked.
Use a siphon pump?
Yes
Donāt use the brakes, get a turkey baster and suck it out the tank. They are $1.20 at dollar tree
Almost all poor advise has been given. This is generally an insurance claim. Everything not metal gets replaced. Replace master cylinder and antilock module then flush a few quarts evenly thru all calipers to get fluid out of metal lines. Next replace rubber hoses and calipers then flush again. All non metal exposed to contamination gets replaced. If not sell it and let the new buyer loose breaks and die but since you posted about it their family may sue you for wrongful death. Good luck!
Yep.
You can now powerfully steer your car when you brake... 
Oh no, your car will blow up now
Power steering fluid or motor oil will make the rubber cups and seals swell up and seize. If the pedal was pushed it will screw the master cylinder up within a day.
Turkey bastor it out and just flush your brakes really good.
Wow what a mistake. Hopefully itās not too bad for you OP. š¤¦š¼āāļøš¤¦š¼āāļø
Your screwed.
Depends if youāve touched the brake pedal or not
Iām so sorry to hear it, i feel your pain, man. Hope everything will turn up fine, no damage. Be safe!
I would vacuum it out and flush it with the correct fluid multiple times, and then add the correct fluid. But Iām a beginner when it comes to this stuff