Why I stopped guessing at brake fluid and bought a $12 tester after my pedal went soft in Denver
Last Tuesday I was bleeding the front brakes on my 2004 Civic in my buddy's driveway in Denver when the pedal went soft on me halfway through. I always thought dark fluid meant it was fine to top off, but a guy at the parts counter asked me when I last checked the water content and I had no clue. He showed me a $12 tester that lights up green, yellow, or red, and mine lit up red at 4 percent moisture. I dumped the old fluid, bled all four corners with fresh DOT 3, and the pedal came back firm by the third pump. Has anyone else had a tester read bad and still run the fluid anyway, or is 4 percent really the point where you swap it?