hey my dads 2007 quad cab 4x4 has a serious brake issue as in they go to the floor.no leaks visible,feels like a bad master cylinder,but am unsure if ABS system could cause same affect.the truck has just over 36,000 miles on it,had to have swaybar links and 1 tierod end replaced under warrentee not very happy with issues this early on.not built like 1st generation from what I can tell.any response would be great,thanks