I would agree with the other posts - sounds like boiling fluid, but that is only a symptom of other problems. A seal problem usually also shows itself with fluid loss. To be safe, rebuild the calipers, use SS lines. You might also rebuild / replace the master cylinder. I use Motul 600, Hawk Blues all around, and a brake bias adjuster. Use a screen over the air ducts and don't be too conservative on your braking points - the longer you brake, the shorter the time for cool air to get to your rotors.