I have had this car since November, and when I got it the pressure plate, flywheel and slave cylinder had been replaced. After driving it about a week the clutch went to the floor, the result was a broken master cylinder so I replaced it, a week later the same thing happened again so I replaced it again, it just keeps happening all within exactly 7 days and now I've replaced the master 5 times going on 6 (the last 4 of which I had my mechanic put in) and on the last time it was replaced we had the slave cylinder done as well. Not to mention completely bled the system each time. The last couple of times we noticed when it did give out, we open the reservoir and the fluid is black and like jelly. What would cause this?