Chevrolet: Blazer Transmition, s10 blazer, clutch plate

Question
I was driving my S10/blazer 2000 model at 50 M.P.H., I went to drop the cluch to get out of gear and i heard a thump(loud). The car no longer has any clutch pressure and it shifts freely when the engin is turned off, I also noticed a vibration in the pedal when i press it down riding down the road. I just need the general idea of what might be wronge with the transmition. The transmition has had previous troubles with the cluch e.g. hard to get into gear having to press to the floor.

Answer
Hea  Jason;
           Well if it is the clutch , it could mean you might need a new clutch plate and also a new pressure plate , the throwout bearing could have went , it could be a few things , the only way is you will have to remove the tranny and look to see what has blown or worn out. it could just be a small thing like the throw out bearing, but I would not drive it like it is , you could do more damage to the tranny or even blow it or break off a few teeth.I think it might just be the throwout bearing ,or the clutch disc. is worn out. ok
Roger ,but again I would not drive it like it is.