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How to completely change brake fluid?

After reading another post on here, it got me to thinking that I need to change the brake fluid on this new to me 93 S10 Blazer I just bought (it’s very dark practically black).



Do you just syphon out as much as you can from the reservoir, replace and then bleed each caliper 'till it’s clear? Any shortcuts to make it easier for a one person team?

Do you just syphon out as much as you can from the reservoir, replace and then bleed each caliper 'till it’s clear?

Yeah, that’s about it. It’s really a two-person job: one guy to work the brakes, the other to open and close the bleeders. It’s boring, but not terribly challenging for the “inside” guy. (Remember to replenish the master cyl resevoir as you go, or you’ll have to re-bleed the entire system!)

Any shortcuts to make it easier for a one person team?

They do sell check-valves for the bleeders, so one person can just step on the brakes, making it a one-person job. I’ve heard mixed reviews of these. For quite a bit more $$$, they have contraptions that will power-bleed “backwards,” from brake to resevior.

My recommendation is to have a friend help you, and pay him back in a friendly fashion…

Use a battery filler and suck out most of the old fluid, There is no need to let it go through the lines. Fill the m/c and leave the lid off. Remove the tires and crack open 1 bleeder at a time and let it run until the fluid is clear. Do that for all 4. If the fluid will not flow remove the bleeder and clean it out and the fluid will start coming out the screw hole, replace the bleeder for a controlled fluid flow. If you want it done in a hurry use the 2 person method.

My way is called gravity bleeding and it works. As long as you do not let the m/c go dry no air will enter the lines.

Thanks to both of you. Nice to know all the options one can do.

At Brake Masters they liked us to have a gravity bleed going while you had a rotor turning and then in the meantime be installing pads or shoes.