Found a stat about brake fluid that has me rethinking everything I thought I knew

So I was reading through some old service bulletins from Bosch the other day, not really looking for anything specific, and I came across a stat that said over 60% of brake system failures start with moisture in the fluid, not worn pads or rotors lol. That caught me off guard because I've always been about checking pad thickness first, you know? I've been turning wrenches for about 7 years now at a shop in Austin and I've never once seen a guy test the fluid's boiling point during a routine brake job. We all just bleed it if it looks dark and call it good. But this bulletin had a chart showing how just 3% water content can drop the boiling point from like 450 degrees to under 300 degrees, which is crazy when you think about hard braking on a downhill. So now I'm wondering, are we all skipping a crucial step here? Do any of you actually bust out a tester and check moisture content every time, or is that overkill for daily drivers?

2 comments

2 Comments

seth6831mo ago

That 3% water stat is brutal, I keep a cheap tester in my box now. Do it on every car that comes in, takes 30 seconds and saves a ton of headache later.

nancybailey1mo agoMost Upvoted

That 3% water stat catches so many people off guard, I learned the hard way after a customer came back with a clouded headlight I'd already sealed. I bought one of those cheap testers too after that, and now I feel like a detective every time I pull it out on a car. It's funny how a little plastic tool makes me look like I know what I'm doing, even when I'm still figuring things out myself.