There are physical differences in the slaves. I don't remember what it was with the first failure (which visually a oring let go). Chuck (SHO-N-GO on the SHOforums) said he saw a difference in this one too before he installed it. I'll have him do a comparo, the next R&R and if possible snap some photos as well. Both times it has done this a brand new clutch kit and flywheel have been installed (SS HiRevs Jr & SS Flywheel first time, and SPEC Stage II and SPEC flywheel this round). I spoke with SPEC with and they said they only use Ford OEM parts.
