So when I was leaving a parking lot, before I got out onto the street my clutch pedal sunk to the floor without any strange noises or anything. I got out of the car, checked for fluid leaks but there were none. I tried to pull the pedal up from the floor and that worked, but then it wasn't incredibly stiff and I couldn't push the clutch down without pushing really hard and it wouldn't disengage the clutch.

The car has an Exedy HD twin disk installed. I'm just hoping for some opinions on what it could likely be. Admittedly I was driving somewhat hard recently (nice weather...) but the clutch was showing absolutely zero signs of problems and was working perfectly. The shop I took it to says something broke within the clutch assembly and the trans has to be taken out for $1200.

The clutch has around 40k on it so I'm going to get a rebuild kit anyway along with a TOB. Should I be able to get away with just buying new clutch plates or will I have to get a new pressure plate and intermediate disk as well?

 

I think this is pressure plate related since there's no feedback from the pedal. Everything else in your clutch could be just fine really.

Are there any noises from the transmission?

 

Not that I noticed.

 

Most likely a master slave cylinder problem. I would check that before anything else.