Brake fluid system needs flush?

Well, one thing that should be taken into account which is one of the most overlooked problems with brake fluid, is its hydroscopic, meaning for its whole life it seeks or attracts water wherever it is ie. The air like a magnet so the longer you use it the more water accumulates in it until the fluid loses its ability to lubricate properly and since water is heavy it constantly migrates downward by gravity ending up down at the wheels where it speeds up the corrosion process of the brake components and robs the system of crucial hydraulic pressure. The good thing about it is brake oil is cheap and easy to flush out and replace. So, yes, " it can't hurt to flush and change it completely every once in a while. Good luck.

Well put "MECHTRIX" thanks for answering :)

Also, here is a guide which has a video to help you see what needs to be done:

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

Let us know if you need anything else.