-- My vat of used brake fluid shows 2%.
Vat of used brake fluid?
Around here, brake fluid gets flushed when the seized calipers get replaced... oh every few years or so. Road salt
Got a brake fluid moisture tester
- Thread starter eljefino
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Vat of used brake fluid?
Around here, brake fluid gets flushed when the seized calipers get replaced... oh every few years or so. Road salt
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This is what's wrong with the internet. Moisture-content is NOT over-rated. Moisture-content forces a chemical reaction, which in turn makes fluid acidic. Acid leaches metal. Thus metal content is the product of 'over-rated' moisture-content. Metal is the product of acid. Acid corrodes components and tears seals. Lest we forget the water boils.
Moisture-content is over-rated. Right.... I see. Very good.
This is like the other brake-fluid myth that is forever spouted on here. It has the feds put a ban on color brake-fluid, this when the feds did no such thing. Be clear, no one ever uses DOT brake-fluid. You've never seen it, you never will. Because, break the seal and it's not DOT fluid. Brake-fluid can be any color. It might not be the 'right' color however the typical color for brake-fluid is brown.
And those cheapo brake-testers are not reliable, simply because formulations differ. Hence you can't calibrate the things. The pricier fluids are high-resistance when new. Thus these testers would indicate 4% or higher from fresh fluids.
Use a calendar, it will not lie.
As you were.
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This is what's wrong with the internet. Moisture-content is NOT over-rated. Moisture-content forces a chemical reaction, which in turn makes fluid acidic. Acid leaches metal. Thus metal content is the product of 'over-rated' moisture-content. Metal is the product of acid. Acid corrodes components and tears seals. Lest we forget the water boils.
Here you go Bloke-
From Ford engineers- they should know (more than you...)
Quote from Phoenix Systems-
"What about moisture in brake fluid?
Interestingly, moisture is not the main contaminant that causes brake system problems, though thought to be the main problem by many industry professionals. Research by the Ford Motor Company indicates moisture contamination of brake fluid was approximately 1% in test vehicles that had been in service as long as 7 years. Moisture testing is recommended only for severe-duty vehicles." ( These tested vehicles were in junk yards around the country under widely varying climatic conditions.)
Phoenix Systems provide alot more on this topic if you care to read. Interesting quote from Bendix- thanks
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I bought one of these that looked like the OP's from Amazon a while back. I opened a brand new bottle of prestone brake fluid - was a couple years old but still had the silver safety seal. Poured it in a cup and tried it - was just looking to calibrate - and I was going to add a little water to make sure the thing worked, but with the new fluid it gave me like 3%. ????? So I tried what was in my truck, and it was a little less - like 2%. This thing must not work - returned it.
Bought what looks to be the same one from ebay - tried again, same results.
Went to walmart, bought a new bottle of brake fluid. Tried it. Was worse yet. Said it had 3% water - new bottle, off the shelf, with safety seal. Still said what was in my truck was better?
I ended up more confused than before.
Bought what looks to be the same one from ebay - tried again, same results.
Went to walmart, bought a new bottle of brake fluid. Tried it. Was worse yet. Said it had 3% water - new bottle, off the shelf, with safety seal. Still said what was in my truck was better?
I ended up more confused than before.
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Yes, Ford and Phoenix say the same thing. I'll type slowly.... Phoenix System sell a pH test strip, branded 'Brakestrip' , its existence verifies my words. It tests for acidity. Oddly, that'd be what a pH strip does?
For those without an English education pH is a measure of acidity/ alkalinity.
The litmus test?
I refuse to believe that's not taught in US schools.
The water degrades fluid to acid. Moisture is not the main contaminant to cause brake system problems, it's the product of the moisture, acid. And the product of the acid.... metal. Phoenix measure pH. What part did you not 'get' first time round?
And there's nothing so wrong with those cheapo testers, more they're not reliable because they don't test what we really need to look at. That'd be pH.
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What part don't you get? Phoenix says moisture is not the problem. If the driving force of the degradation process is moisture and it's not there ("not the problem"); how is this "acid" formed? Ford only found miniscule moisture and "acid" was not mentioned in their report. If "acid" is the issue, the engineers must have overlooked it. And please- lose the condescending attitude.
And I'm not going to make your day arguing over this.
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Yes, I see that. I've coloured pencils, would it help if draw it for you?
The green one's nice.
The green one's nice.
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Just have to buy a few different brands of fluid and use that same tester if you really don't mind spending the money.
I use both the device and phoenix copper test strips. And about to do new pads and rotors on both cars at 60k and 90k (2nd replacement) along with fluid flush using a pressure bleeder. One vehicle is dot 3, the other gets ATE dot 4. Most times the phoenix strips show no copper and moisture has always been 1% or less except last flush was 2%. This time one car is showing 10ppm copper on strip. Last changed fluid on that vehicle in 2021 using ATE, so a little surprised. But, the car is 20 years old.
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Suggest this to Project Farm.
If you want to be really anal and possibly more accurate, you could take a sample, put it in a beaker or pot and heat it up to boiling and note the temperature at which is starts to boil. The closer it gets to water's boiling point (212F/100C give or take with altitude, etc.) the more water content it has. Once you have the boiling point, you can compare with this chart: https://www.misco.com/when-to-change-your-brake-fluid/
OR you can follow what the article says, which is that generally, brake fluid absorbs about 1% water per year. So a 3 year change is logical. Or just don't do it; whatever. Personally I find it pretty easy and taking the small amount of effort to do it gives me some piece of mind with all the complexity and parts of modern brake systems (ABS systems can get pricey real quick) just to keep the possibility of corrosion or degradation minimal. I rarely changed mine in the "old days" too, unless I had to put on a new master cylinder, or line or something like that, but these new systems don't have as much margin for error in my opinion, and when they go bad and need work it is more complex and more expensive, so I'd just as soon avoid it with something that is really not hard to do. JM2C
OR you can follow what the article says, which is that generally, brake fluid absorbs about 1% water per year. So a 3 year change is logical. Or just don't do it; whatever. Personally I find it pretty easy and taking the small amount of effort to do it gives me some piece of mind with all the complexity and parts of modern brake systems (ABS systems can get pricey real quick) just to keep the possibility of corrosion or degradation minimal. I rarely changed mine in the "old days" too, unless I had to put on a new master cylinder, or line or something like that, but these new systems don't have as much margin for error in my opinion, and when they go bad and need work it is more complex and more expensive, so I'd just as soon avoid it with something that is really not hard to do. JM2C
I sent him an email
Todd emailed me back in about 15 minutes, believe it or not. Just thanked me for the suggestion (maybe it was just an automated response). Anyway, we'll see if he does it. Like many of you, I'm subscribed to alerts for his channel.
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My friend Rey says the same thing about tire pressure. The only time it’s checked is when a shop puts new ones on his car. I think he’s in his late 50’s and he has had many cars and has never had the need to add air. He asked me for what possible reason did I spend $22 on that Jaco that can go to 0.1 psi