Originally Posted By: Kaie
Originally Posted By: unDummy
Its all about the moisture. Why replace wet brake fluid with new wet brake fluid?
Always put the opening date on the bottle with a sharpie or magic marker.
Depending on location, as humidity levels vary, I wouldn't use an open bottle after a year.
Ways of utilizing that open bottle of brake fluid are simple. S
imply siphon/refill your reservoir a couple times a year and you won't ever have 'old' brake fluid sitting around. Top off the reservoir as needed.
your brake lines are a dead end. Meaning theres no return line. Yes there will be some movement in the fluid. But i highly doubt its enough to do what you are suggesting.
Quick....someone invent diffusion!!
Also, the post only suggested a way to utilize the open bottle, he actually didn't say anything about the effects of doing so (although removing wet and dirty brake fluid and adding clean and dry should do
something).
There's probably enough movement over time that there won't be a huge gradient of old vs. new fluid from the master cylinder down to the calipers.