my brake master cylinder is shot and is leaking. could it be because i used a DOT3/DOT4 formula instead of strictly a DOT3? i originally used DOT3 and had no problems. i switched to the DOT3/DOT4 formula and it started leaking. not sure if it was just coincidence. if i revert back to the original, do you think it'll fix the problem? or do i have to shell out $200 for a master cylinder? thanks guys.