Power steering fluid in brake system

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TommyJ1980

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1998 K2500 pickup - So yesterday, as I was finishing up replacing the steering gearbox and steering shaft, I realized that about two weeks ago, in an effort to fix developing issues with the steering system, I had added power steering fluid, not to the power steering reservoir, but to the brake fluid system. Not knowing what the effects of this would be, I thought to myself "way to go dumbass", and carried on calmly, thinking something along the lines of, "how bad can it be?".....Well, today I was rewarded with brakes that thankfully locked up while parked. It was more like having the parking brake on, than a total lockup, on the front driver side. I went and picked up a pair of front calipers, then started doing some reading, and then saw that in fact, this a major issue. I bring it now to you gentlemen, (and any ladies who may be present). I am on my way to pick up new hoses, and master cylinder. I guess my main question is, what all do I need to do to the rear brakes? They are stock drum type brakes, I don't know that anything's ever been done to them since new. I thank you in advance for any wisdom you may provide. T.J.
 

Caman96

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ABS system, proportioning valves, rear wheel cylinder’s aside from master cylinder and calipers. All rubber is toast in system. This was a disaster, sorry to say.
 
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GoToGuy

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This is perfect example of " all seals are not the same material ".
If this had happened on the highway , 65 miles an hour.. you might never have started this thread.
Anything brake system rubber ( not actually rubber, a synthetic blend brake fluid compatible) must be replaced.
Rear wheel cylinders, just order new ones, same with calipers, the ABS is toast, gotta fix that too. And master cylinder. Brake lines too.
I don't know if the proportioning valve has rubber in it. You'll have to research that one.
Good luck.
 

TommyJ1980

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yes, I’m thankful the circumstances weren’t worse. How come I’ve never heard of this before, I’ve been hanging around things with motors for a while now. Public service announcement anybody? what are these proportioning valves you speak of?
 

TommyJ1980

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The other reason it wasn’t probably worse is that I didn’t put very much in there, just a splash or two to “top it off”.
 

Supercharged111

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How is trans fluid so hard on rubber brake components? Both are hydraulic fluids. I'm shocked a simple purge isn't enough to make OP whole again.
 

Caman96

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Seems like if your brakes have already locked up, then “rubber” components have already been compromised. I’ve heard shops won’t touch it at this point unless all of system is replaced.
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TommyJ1980

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Wow, that's wild. Well OP, now's as good a time as any to ditch the ABS pump.
This whole thing is getting a bit ridiculous at the moment. I’m going to leave the ABS module alone, replace the master cylinder and calipers and flush new fluid through the system to all four wheels, and attempt to put it back together and drive it 1/2 mile to its front end alignment at 2pm, which couldn’t be done yesterday because of frame plugs that have to be cut out. Hopefully it makes it to that and back home, then I can deal with the rear wheel cylinders and valves, and take a look at this custom procedure I’m reading about to bypass the ABS pump, which looks to be a pain in everybody’s a**. Thanks for all the input, wish my luck, I won’t be doing over 25mph till I get this whole thing troubleshot.
 
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