I can second @SteveS... do NOT hold the clutch pedal down at traffic lights for the Fiesta ST.
There has been enough members reporting clutch hydraulic issues that I've considered it legitimate and not customer abuse or just, "Murphy's Law".
I did this for well over 250,000 miles on a prior car but its slave cylinder was on the outside of the transmission, attached to the bell housing; and never had issue an issue. I had to replace only the clutch master cylinder once in its 327,000 mile ownership. (leaked brake fluid onto the floor of the passenger cabin) The slave never had to be replaced. My FiST is <80k but could tell the clutch hydraulic was starting to behave a little differently. I quit holding the pedal at lights and so far I haven't detected the behavioral change again; though it has mostly been parked since Oct 2024.
The slave cylinder is inside the transmission and the seals seem to be vulnerable to the additional heat transfer that occurs when pushing the clutch spring. Seal failure, which can leak either by pushing out fluid or allowing air entry, for the slave cylinder means pulling the transmission. If there's anything we can do to stave that off, I'd certainly do it.
There has been enough members reporting clutch hydraulic issues that I've considered it legitimate and not customer abuse or just, "Murphy's Law".
I did this for well over 250,000 miles on a prior car but its slave cylinder was on the outside of the transmission, attached to the bell housing; and never had issue an issue. I had to replace only the clutch master cylinder once in its 327,000 mile ownership. (leaked brake fluid onto the floor of the passenger cabin) The slave never had to be replaced. My FiST is <80k but could tell the clutch hydraulic was starting to behave a little differently. I quit holding the pedal at lights and so far I haven't detected the behavioral change again; though it has mostly been parked since Oct 2024.
The slave cylinder is inside the transmission and the seals seem to be vulnerable to the additional heat transfer that occurs when pushing the clutch spring. Seal failure, which can leak either by pushing out fluid or allowing air entry, for the slave cylinder means pulling the transmission. If there's anything we can do to stave that off, I'd certainly do it.
i usually coast up to lights in neutral...i guess ill have to pay attention to how i chill at red lights now.
