It seems as if there is a leak somewhere, as my brake fluid tends to slowly disappear, although, there are absolutely no signs of leakage anywhere.

Does anyone have any advice? Is the BMC corrupted? Should I get it replaced?

 

Check it while someone is pressing the pedal. (Wear safety glasses so you don't get squirted in the eye)

 

is the pedal real squishy?

 

my pedal has to go all the way to the freaking ground before my brakes engage, i hate it. i have to go through and bleed my brakes, then if it still doesnt go away then i'm going to have to look into the BMC. thankfully my GXL doesnt have ABS

 

when your bleeding them, if it just seems to pull an endless amount of air (like mine did). the BMC is probably leaking and bad. my braking improved dramatically after replacing it.