Hi all
So I've had this problem with my 4Runner ever since I've bought it. No matter how much I've changed fluid and bled my brakes, my brake fluid always turns green after a short period of time, and I'm curious if anybody can think of a reason why or if anyone else has the same problem.

My car still stops alright, but whenever I replace the fluid and bleed my brakes the pedal is MUCH firmer - then slowly the pedal gets very soft as the color changes and eventually I need about twice the pedal travel just to bring it to a stop, almost using all the travel everything I got.

Over the past 4 years I've bled all four corners easily over 10 times and have gone through countless bottles of fluid. Every time I bled them I wouldn't stop until the fluid coming out was just as clear as what was going in, but the longest it seemed to stay away was maybe 2 months at absolute best before it all turned just as green. I realize there's probably a good amount trapped in the ABS box doing this, but I don't see a way of how you would/could clean it out. Is it just time for a new one maybe? Even then I very rarely have ABS activate so it shouldn't be circulating, right?

I ask because if you do a google search for causes behind green brake fluid you'll get every possible answer under the sun, everything from "there's algae in the system" to "you gotta sacrifice a goat" - and not a single one of them related to 4Runners, or really any cars from the 90s for that matter.

Pic related is my master cylinder. Green as a Jolly Rancher, except this time it's still pretty clear; typically when I bleed my brakes it comes out looking like swamp water. This fluid has only been ran since mid September, and my ABS has been off the entire time (haven't gotten around to replacing the front left sensor)

Sorry the pics are so huge, I tried to downsize them to 20% but I guess that's just how it goes now.

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