at this point me I would cap the front lines AT the calipers (might take some doing to get the right fittings) & see if the system is now high and tight. (if so) that'd tell me the air is in the calipers & some are a bear to tilt em just right to get the air to come out at 12 o'clock. EDIT I'd clamp the front hoses with (2) vice grips with protection of course for the serrated edges & you'd know in minutes the answer. Might not be the best for the hoses but I dont think it'd wreck em