Any idea what this slimy looking green stuff is in my brake fluid reservoir. It looks like its confined to the strainer, but I have not yet remove the strainer to check below.

The brake fluid in the reservoir looks light brown. I was planning to flush the system soon anyway, but was not expecting to see this gunk when I removed the reservoir cover.

unless your cap is broken and all kinds of crap went in.

what you're seeing is the residue build up in your brake system.

u should flush your system ASAP. at least 3 times.

Wow, never saw anything like that before. I can only speculate that somehow microbes were able to colonize there or maybe at some point 2 incompatible fluids were mixed. Did you buy the car used?

I would be thinking about removing the resevoir and either replacing it or thoroughly washing it in some way that would be compatible with the braking system. I wouldn't want to be working any of that slime into the system.

I bought the car brand new. I don't recall adding any brake fluid over the years, if I did, it was Preston DOT 3.

Fluid was supposedly change by the dealer a couple of years ago during maintenance. I think all the slime is just above the strainer, so I'm planning to clean out the strainer and reservoir before flushing the system. Car brakes fine ..... I wonder if I'll feel any difference after the flush ..... of course that might include new brake pads too, depending on how they look.

Use DOT 4 fluid. Is much better than 3.

Dont use anything above tho.

looks like someone mixed in dot 5 fluid.

if its just in the strainer, flush the system and you're good to go.