FLUID LEVEL RUNS LOW ABOUT EVERY 30 DAYS. RESERVOIR RUNS LOW. NO LEAKS DETECTED WHEN INSPECTING THE BRAKES, BRAKE LINES OR FITTINGS. NO PROBLEMS STOPPING. BUT A ROARING SOUND WHEN STOPPING AT HIGH SPEEDS
That's a really slow leak and may not show up with a visual inspection. One commonly overlooked place to look is at the back of the master cylinder. Fluid will get sucked into the power booster and will be burned in the engine. You may need to pull the master cylinder loose to check for wetness around the push rod.
January, 16, 2014 AT 6:40 PM
I'd also make sure you didn't have a seeping leak at one of the caliper piston boots. It may be leaking and burning off in the caliper.