Power steering fluid in brake fluid

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JackZilla

JackZilla

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Orting, Wa
Bought a new LC last night. Got a really nice deal on it, but for good reason. PO decided to top off his brake fluid with power steering fluid. Calipers are brand new as of March so I'm assuming the brake fluid level would have been full so I can't imagine that the PO was able to put that much power steering fluid into the brake system. It was enough to cause the calipers to tighten up and the brakes are now dragging. Hasn't been driven since this started.

Question is this: what are the possibilities of salvaging my brake lines and any rubber fittings inside of the calipers by completely pumping the brake system dry an refilling with brake fluid? Or, should I just start replacing things now?

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Both power steering and brake fluid are hydraulic oils, I suspect if you flush the system there will be no ill effects on the brake components.
 
freshspecbluegt said:
Both power steering and brake fluid are hydraulic oils, I suspect if you flush the system there will be no ill effects on the brake components.
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Good to know. I'm hoping it's a pretty straight forward fix. She's still going to need a new power steering pump, sooner than later.
 
JackZilla said:
Good to know. I'm hoping it's a pretty straight forward fix. She's still going to need a new power steering pump, sooner than later.
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Brake fluid and power steering fluid have different properties though so make sure you flush the system thoroughly.
 
I agree with^^^. If you do a really thorough bleed and flush, should be fine. Don't forget to back your calipers put all the way to get the PS fluid out of them as we'll. I would think you could disconnect all the hoses, press the brakes with the truck running and keep doing it til the reservoir was empty, then do that a couple more times with brake fluid and should be good to go. Thoughts?
 
The best way would be with a power bleeder. Start with the caliper furthest from the master cylinder and flush until it's clear. I would not run the master empty as you will need bleed the master which is more work. Also if doing the pedal pump method don't let the pedal hit the floor as you can damage the piston seals leading to a leaky master cylinder.
 
Good info. If I just bleed the lines like a person normally would, pumping the brakes and opening up the bleeder valve, will that eventually get all of the nasty stuff out of the lines and calipers?
 
Brake fluid is not oil based. In the cases that I have seen, oil in the brake system doesn't end well, seals swell causing pistons to stick, etc. I would suck the fluid out of the reservoir (turkey baster), remove it, wash it out, then refill and flush bleed. Chances are, seals (at least) are going to need replacement.
 
Yep Tools is right (as usual).

Sorry I gave you bad info. Brake fluid is glycol-ether based and not and oil. Both are hydraulic fluids but both are not oils.
 
I vote for what Tools R Us suggested. Remove as much contamination out the reservoir as possible, first. Flush bleed. Check hard for seal failure.
 
If you don't have a turkey baster to remove the fluid from the brake reservoir, I found that a typical hand soap dispenser works well, preferable the disposable variety and not the :princess:'s Snow Man Christmas ornament hand soap dispenser:o. Just make sure to clean the soap off before inserting it into the reservoir. I also found the soap dispenser to be a handy container to pump the fluid into.
 
Completely bled the system with new brake fluid. Brakes work great. Nothing seems to be leaking as of now but I'll give it another glance over the next few days to see if the calipers are leaking.
 
You might want to check for brake line swelling. Had a similar situation w Nissan lines. Bled the system with gravity and new fluid flush , and replaced the swollen runner lines with stainless for $100. Good reason to go stainless! The rest of the system is metal tubing why not the lines, right?! Good inexpensive quality insurance that doesn't take too long to diy
 
FJC80 said:
You might want to check for brake line swelling. Had a similar situation w Nissan lines. Bled the system with gravity and new fluid flush , and replaced the swollen runner lines with stainless for $100. Good reason to go stainless! The rest of the system is metal tubing why not the lines, right?! Good inexpensive quality insurance that doesn't take too long to diy
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I looked at all the rubber lines while I was bleeding the calipers. They all looked normal. But over the next few days, I'll continue to keep an eye on things.
 
Aggiesdm said:
I agree with^^^. If you do a really thorough bleed and flush, should be fine. Don't forget to back your calipers put all the way to get the PS fluid out of them as we'll. I would think you could disconnect all the hoses, press the brakes with the truck running and keep doing it til the reservoir was empty, then do that a couple more times with brake fluid and should be good to go. Thoughts?
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Well thanks for the additional info. I always learn stuff from you guys.
 
Spoke a little too soon. Brakes were working great, but after an extended test drive they started dragging again. Got it into the garage and let it sit for a few minutes and the brakes released. This morning I opened the reservoir and could see small bits of PS fluid still floating around in the clean brake fluid. I'm not ready to give up yet. Going to do the whole process over again. If I need to, I will do it a few times. Hopefully this gets the last bits of PS fluid out of the system.
 
And check your caliper bolts. I just had one of mine come out yesterday and all the others were close to falling out too. Might as well tighten them down since you'll be in there.
 
wpns4l said:
And check your caliper bolts. I just had one of mine come out yesterday and all the others were close to falling out too. Might as well tighten them down since you'll be in there.
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Didn't think about that. Good idea. These are new calipers from Les Schwab so they should be alright, but you never know.
 
Unfortunately, ANY oil in your brake system has contaminated the ENTIRE system. ALL rubber products must be REPLACED and ALL steel lines MUST be THOROUGHLY flushed with a solvent-based cleaner (Brakleen) (or better yet to replace the brake lines.)

Oil will make the seals in the master cylinder, calipers, LSPV, and hoses to swell and either swell shut (lines) or swell to the point of leaking (calipers) with a CATASTROPHIC failure.

I know this because we had a hired hand that did this to an International Truck used on the farm (Hydraulic oil... brakes are hydraulic thought process...) and the brakes all of a sudden started dumping brake fluid everywhere. In this case, it was a hydraulic over air system, so when the hydraulic system failed, the brakes didn't work AT ALL. I had to help rebuild the system and after flushing the lines over and over with Brake Cleaner, then fluid, I would suggest replacing the lines, as it would have been faster and cheaper in the long run.

In this case, the wheel cylinder seals swelled to over 2X the original size by the time it was done.

Stop messing with it HOPING that it will heal itself. This will be a continual problem unless you bite the bullet and do it right. Replace all the brake system or unload the truck. This will be a HUGE safety concern. I hope you got it CHEAP!

Sorry to hear about the problems! I wish you the best!
 
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