Hi All,

While at the track on Sunday, May 6th, I was having a clutch pedal issue. It was as follows:

Heading into turn 3 @~125mph 5th gear, engage clutch pedal, downshift, release clutch pedal **only comes back ~50%.**

Prior to turn 3, I am at 125-135mph sustained for about 10 seconds (AutoClub Speedway Roval Course). I am reading that it could be my OEM master cylinder not handing the heat? Any thoughts?

This ONLY happened on turn 3 after sustained speed in excess of 125mph.

 

Could be MC. Could be something else. When was the last time you bled your clutch fluid?

 

Never. The car had 24k miles when I bought it. I did not touch the clutch fluid (it is clear). I did not have this issue on my first 5 track days with the car.

I will bleed it this week and see if that helps. Next track day is in two weeks.

 

I would give it a good bleeding and start there since it would be the cheapest fix. I like Motul 5.1 since it has a higher boiling point than the OEM DOT 3. I know some that track their cars use RBF600, but I believe you need to change it more frequently.

If bleeding it doesn't work, then you've eliminated that as an issue. When I had pedal drop issues, I changed out the Master for the Wilwood HD and it solved the problem you're having.

 

Awesome, I will follow those steps. Thanks!

 

I had a bunch of dark gunk in the bottom of the reservoir when I flushed all the fluid out. I believe there may be some type of MC rebuild kit for the OEM, but I just ended up replacing it. Either way - good luck!

 

I had the "typical" clutch pedal issue in my 06, same symptoms as you described in track days and also during very hot days in street driving (can be 120 degrees where i live).

How I fixed mine:

1. Replaced slave
2. Bleed with RBF600
3. SS clutch line

Car has 100k miles and after several track days in southern california heat the issue has not come back.

 

Yes, high temp fluid is a must for the clutch. Same stuff for brake fluid. ATE, Motul, ect