I was driving along the other day but when I came to a stop and pressed the clutch pedal it just stayed at the bottom, after trying to find a problem for ages and replacing the master and slave cylinder the clutch was too hard to push, it was then I realised that the slave cylinder is already pushed out as if its pushing on the fork in the gearbox which just moves freely without the cylinder there, is there a common problem that I'm unaware of, i'm not sure if the fork has just come off, the thrust bearing has failed or something more serious, any ideas what could of happening before I take the box off??

cheers all !