ATF added to brake fluid. What, specifically, are the implications for ABS?

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ATF and brake fluid dont mix, ATF floats on top, so that 1 ounce of ATF you added did no harm to anything. Simply suck it out and put in Brake Fluid. No need to replace any rubber parts.
 
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aren't most brake fluids not oil based and hydroscopic meaning it wouldn't wanna mix with atf. You should flush it if you've got some sponginess. I flushed my system by putting hoses on the bleeders and bottles and just pumping it all out. i used a brake bleed kit and pumped fluid back in and would turn the truck on a couple times during the fill and prime and now my brakes are like new just from that alone. no more air or old fluid.
 
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ATF and brake fluid dont mix, ATF floats on top, so that 1 ounce of ATF you added did no harm to anything. Simply suck it out and put in Brake Fluid. No need to replace any rubber parts.
You cant go by a static test, the operation of the MC is anything but static, step on the brake pedal with the cap off. Stuff gets mixed up in there every time you apply the brakes and it only take a minuscule amount to cause damage.
For that reason I suggested removing the MC and checking the seals, if those are okay then the rest of the system is more than likely okay.

For those interested.

 
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You cant go by a static test, the operation of the MC is anything but static, step on the brake pedal with the cap off. Stuff gets mixed up in there every time you apply the brakes and it only take a minuscule amount to cause damage.
For that reason I suggested removing the MC and checking the seals, if those are okay then the rest of the system is more than likely okay.

For those interested.

1 ounce of fluid in the reservoir is not going to be sucked down into the MC.
 
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How do you know that? How big is the reservoir? Was it really an ounce or less? You cant answer any of those questions with any certainty and neither can I, are you going to take responsibility for it failing if it does? Brakes are critical and nothing to be taken lightly, it should be checked out thoroughly and flushed at a minimum.
 
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How do you know that? How big is the reservoir? Was it really an ounce or less? You cant answer any of those questions with any certainty and neither can I, are you going to take responsibility for it failing if it does? Brakes are critical and nothing to be taken lightly, it should be checked out thoroughly and flushed at a minimum.
You know what, getting significant oil in the brake fluid, is going to be noticed quickly, if anything happens at all. So if it has not done anything in a week of time to the system, then nothing untoward is going to happen months forward in the future. Common sense should prevail, not panicky feelings. I go by what the thread starter SAID, and said it was an ounce, meaning a small top off of the reservoir was done. IT WILL NOT MIX, suck it out and refill with brake fluid. Better to do that, then do it again in a day than flushing the whole system. If you flush it down then your certain to get some ATF going into the system. Suck it out, use a paper towel dry it out, then refill.
 
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ATF and brake fluid dont mix, ATF floats on top, so that 1 ounce of ATF you added did no harm to anything. Simply suck it out and put in Brake Fluid. No need to replace any rubber parts.
Oh no it doesn't.....Just did an ins. job on a newer wrangler a few weeks ago.....another shop topped up her brake fluid with ATF, and within just over a week, she had a very low pedal. Master was completely screwed, and it got all parts replaced with rubber. Ins. insisted all parts be replaced, not that we would do it any other way.
 
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You know what, getting significant oil in the brake fluid, is going to be noticed quickly, if anything happens at all. So if it has not done anything in a week of time to the system, then nothing untoward is going to happen months forward in the future. Common sense should prevail, not panicky feelings. I go by what the thread starter SAID, and said it was an ounce, meaning a small top off of the reservoir was done. IT WILL NOT MIX, suck it out and refill with brake fluid. Better to do that, then do it again in a day than flushing the whole system. If you flush it down then your certain to get some ATF going into the system. Suck it out, use a paper towel dry it out, then refill.
Common sense dictates to empty the reservoir first before flushing it through.
 
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