Fred R. C4S

I recently reported a strange problem with my clutch. While depressing the clutch to make a downshift, I felt a slight jolt through the pedal, and the pedal would only move 120mm, not the 150mm as specified. After pushing the pedal a bit harder a few times, something popped, and full travel returned although the pedal effort just seemed different.

As a mechanical engineer, I know that failures just don't cure themselves. I took the car to the dealer, and told the mechanic to investigate the problem and replace the slave cylinder while he was at it. I had visions of all sorts of odd failures of the throwout bearing, throwout fork, throwout fork shaft, or the needle bearings that support it. I was dreading the thought of having to drop the engine to get at this area.

This story has a relatively happy ending. Seems the problem was a failure of one of the studs used to secure the slave cylinder. It looks like a fatigue failure resulting from the nut not being tight, and the slave cylinder cocking in the mounting. The slave cylinder boot was also damaged. New stud, new cylinder, and everything is good again. No squeaky noise from the clutch actuation, and smooth pedal feel.

The mechanic admonished me that engineers often think of the most complicated, worst case scenario before they have all the facts. I have to admit, guilty as charged.

DJF1

Actually this sounds very correct analysis. I have replaced 3 slave cylinders helping out my mechanic and all were the same PITA to install. The slave cylinder needs a very strong push to get in properly and the front end is not solid but needs to align perfectly and center. All that pressure and force that the two studs have to endure for sure if one nut is loose it will push back , misalign the cylinder and possibly damage the stud.

You are lucky...