Brake fluid replacement and bleeding is something you should do at least every year. Brake fluid absorbs moisture from the exterior, that moisture can create rust inside the brake system making it less efficient. To drain the system you have 2 choices, one is to get your car to specialized shop that can drain it without leaving bubbles in the ABS (if so equipped). This is hard to do.
You second choice is do it at home and try to replace most of the fluid with new one.
Start by getting some decent synthetic fluid, 3 or 4 small bottles is all you need, we here also recommend Mobil or Motorcraft. The synthetic fluid absorbs less moisture and can withstand higher temperatures, a good thing if you race your car.
For this procedure you will need the help of a friend to press the brake pedal while you open the bleeder valves on the brakes. You will also need to place a rubber hose on the bleeder at the brake to pour the old fluid inside a used bottle.
Start with the passenger side REAR caliper, have someone press the brake (or use a jack against the seat and brake.) and open the bleeder slowly until fluid stops leaking, then close it. Ask your buddy to remove his foot from the brake pedal or remove the jack. Repeat this procedure 5 times. Now check the fluid level and add NEW FLUID to the reservoir. Go to the drivers side rear wheel, repeat the process. Do the same at the front, go to the passenger side first then do the drivers side. Don't forget to fill the brake fluid reservoir tank before it gets empty!!!.
Take the car for a spin at SLOW SPEED, and test the brakes several times, increase your speed as you get confident that everything is ok, hit the brakes harder and harder each time. If they feel very "mushy" or soft, try bleeding them again, probably a bit of air got into them.
Something often overlooked: Brake Fluid replacement.
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