As you know there has been problems with both the C5 and C6 including the C6 Z06 where at certain conditions high RPM shifting and clutch pedal will not return to the "off clutch" position.
Due to some "gods" in cyberspace have as we mentioned on other posts about this make wild claims that the whole problem is due to dirty brake fluid and if you clean it often the problem will never occur.
We have always thought those makeing such claims should stick with playing with toy cars.
If any thought was used it is clear that dirty brake fluid cannot hold back the total force of the arms of the pressure plate and in fact changing the fluid often only causes brake fluid to break down due to water in the air.
So all the below is on the slave that has been in out 1999 C5 for 7 years.
Compounding the whole problem is
1. slave design, as seen you can see all the packing (grease) that was in bearing gets heated and pushed out of bearing causing bearing then to have slop movement and the packing to gum up the shaft bearing slides onto.
2. the bearing female shaft slides over the male shaft of base of slave.
3. if you look closely you see flat grooves inside of bearing shaft, there is too much free play and with the packing grease gumming up the make shaft the groove of bearing wear grooves into the male shaft and due to all the slop freeplay the bearing gets cocked and jammed onto male shaft.
4. Notice the heavy wear marks on male shaft, it is easy then for bearing to get coked on an angle and rather then slide back down shaft is jammed, metal to metal.
5. Hose from clutch pedal, notice that even after 7 years with a ton of racing that the fitting at end of hose going into slave is still clean and the hole inside of slave to clutch hose is also clean, no dirt at all.
Add centrifugal force, due to GM making a weak design so those who otherwise could not drive a clutched Corvette could.
At certain high RPMs and due to centrifugal force the arms of pressure plate have less force and with a cocked throwout bearing cannot push bearing back which then would push the fluid back to allow clutch pedal to return to its upper limit.
Once you clearly see how the inside of bearing has lost the bearing packing, how it grooves the slave shaft and the packing grease gumming up and due to freeplay it is easy to see how bearing could get jammed and not return to proper position and dirty brake fluid in no way could cause any of this.
Review the thread as to our findings as to the clutch master design failures at : Master design failure