After searching through all the brake fluid replacement proceedure posts, it seems the recommended way is to mix the new fluid with the old and bleed the lines until the color of the old fluid is gone. I'm wondering though, what if you are replacing the same color fluid? Then how do you know when the old fluid has been bleed out? What is the reason for not just draining out all the old fluid and then filling them back up and bleeding the new fluid in? Sorry if this has been discussed many times but even in all those brake fluid posts I couldn't find the answer to this one.

 

you never want to run the master cylinder dry. you can tear a seal inside if you pump it dry. for example if you replace the MC with a new unit you must bench bleed it first.not just slap it on and start bleeding.

 

bleed it with a full liter of brake fluid. (and make sure a liter comes out). thats all.

a liter is more than enough to ensure a full bleed.

 

yeah, what they said... plus you don't ever want to get air in the brake system if you can help it. by draining all the fluid out, you'll have a hell of a time getting the system back to where all the air is bleed back out.

as for knowing when new fluid comes out, that was the reason ATE had both blue and gold fluids.

good luck... you'll love the results. don't forget to change the clutch fluid, too.

 

Is that why? Haha I always wondered why there were two fluids that were the exact same but different colors. Cool, good to go I guess, just got to get me some speedbleeders. Thanks for the good info.

 

Use a turkey baster or large syringe to suck most of the old fluid out of the reservoir, fill with fresh fluid, then bleed.