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Clutch Issue Recently

Intuit

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South West Ohio
#21
Actually there is a reason for it. Its called a concentric slave cylinder and the throwout bearing is attached directly to the output shaft of the slave eliminating the old school throwout forks. Idea being more compact setup less moving parts. More concise performance.
A lot of modern manuals are being built this way. I mentioned the Z because it was the first time I came in contact with a setup like that. Its become more common since.
It appears the extent of the benefit is the little bit of weight savings from not having a fork run from the throwout to the slave on the outside. In terms of performance for long term daily driving, I've noticed no benefit. Doesn't have anything to do with the location of the slave cylinder, but the clutch from that other vehicle had a better feel, resulting with quicker/smoother engagements after a throw. (mostly has to do with pedal engage height, six-spring Daikin clutch disc) Also, transmission shift forks shouldn't be confused with the fork that the slave pushes on. Shift forks may get chewed, but never heard of the fork going from a slave into a trans with a healthy functioning throwout bearing being damaged. For the conditions that the slave is subjected to, the internal design seems less reliable and *way* harder to access for diagnose and repair. Bottom line, I'd need more information to counter personal experiences and observations. The cost in reliability and serviceability isn't worth the little bit of weight savings.

BTW, never implied that this was an unusual design; never stated that there wasn't a reason for it; hence the question "are you aware". My first exposure was with a late 90s Sunfire. (it failed - though that transmission and clutch were utterly abused by its driver)
 


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Location
Wisconsin
#22
Does anyone have/know all the part numbers I need to fully replace the slave cylinder? I'm pretty damn sure the slave is the reason my clutch pedal sticks and I want to start buying the parts to replace it. Any and all help will be appreciated. Also, I'll most likely be buying the parts from tasca.
 


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Location
Tigard, OR, USA
#23
i had the same problem. Push in the clutch and it would stay on the floor I’d pick it off the flore and it would work fine. Ford fixed it (13k mi ) so it was under warranty. First they replaced the master and that did not fix it. Then they opened it up to get to the slave and found the line has a small split and would periodically puke onto the clutch, fly wheel, pressure plate. They replaced everything including the slave. I wish I would have thrown in a proper LSD when I had the chance
 


Dpro

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Los Feliz (In the City of Angels)
#24
It appears the extent of the benefit is the little bit of weight savings from not having a fork run from the throwout to the slave on the outside. In terms of performance for long term daily driving, I've noticed no benefit. Doesn't have anything to do with the location of the slave cylinder, but the clutch from that other vehicle had a better feel, resulting with quicker/smoother engagements after a throw. (mostly has to do with pedal engage height, six-spring Daikin clutch disc) Also, transmission shift forks shouldn't be confused with the fork that the slave pushes on. Shift forks may get chewed, but never heard of the fork going from a slave into a trans with a healthy functioning throwout bearing being damaged. For the conditions that the slave is subjected to, the internal design seems less reliable and *way* harder to access for diagnose and repair. Bottom line, I'd need more information to counter personal experiences and observations. The cost in reliability and serviceability isn't worth the little bit of weight savings.

BTW, never implied that this was an unusual design; never stated that there wasn't a reason for it; hence the question "are you aware". My first exposure was with a late 90s Sunfire. (it failed - though that transmission and clutch were utterly abused by its driver)
I am not confusing the two, nor do I think anyone will get confused with my explanation. You asked why they had gone to concentric slaves and I explained that the manufacturers elected to do this as they saw it as more efficient.
Now everyone has their opinion on whether or not its better I was explaining. I think you are also possibly over thinking the whole thing. Its the way it is.
 


Last edited:
Messages
142
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156
Location
Wisconsin
#25
i had the same problem. Push in the clutch and it would stay on the floor I’d pick it off the flore and it would work fine. Ford fixed it (13k mi ) so it was under warranty. First they replaced the master and that did not fix it. Then they opened it up to get to the slave and found the line has a small split and would periodically puke onto the clutch, fly wheel, pressure plate. They replaced everything including the slave. I wish I would have thrown in a proper LSD when I had the chance
I have a feeling this is going to be what mine needs and sadly it's going to be coming out of my pocket.
 


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Location
Miami, FL, USA
#28
Does anyone have/know all the part numbers I need to fully replace the slave cylinder? I'm pretty damn sure the slave is the reason my clutch pedal sticks and I want to start buying the parts to replace it. Any and all help will be appreciated. Also, I'll most likely be buying the parts from tasca.
Did you have to end up going this route?
If so, how bad was the damage?
 


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Location
Wisconsin
#29
Did you have to end up going this route?
If so, how bad was the damage?
Ended up just replacing everything. Slave, clutch, flywheel, pressure plate, master, all of it. My dad was able to find a shop to help me out price was. But at full price with labor and parts it's a $2k+ job.
 


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Location
St. Charles
#30
Interesting... I had this same problem early on with my 2015 FiST, but it seemed to correct itself and has worked normally for over three years now.

FB
 


Messages
142
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156
Location
Wisconsin
#31
Interesting... I had this same problem early on with my 2015 FiST, but it seemed to correct itself and has worked normally for over three years now.

FB
How many miles did it have when the issue started? And how many did it have once it self corrected?
 


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Location
Laguna Beach, CA, USA
#34
The clutch slave cylinder has failed twice in less than 45,000 miles on my manual 2014 Fiesta ST, purchased new from dealer in March 2014:
1. January 2017 at 19,875 miles
2. November 2020 at 44,512 miles

On both occasions it failed suddenly: driving along (no mushy pedal, difficulty changing gear or any other symptoms) and suddenly the clutch pedal was stuck flat on the floor, making it impossible to change gears.

On both occasions my wife was driving. The first time she was in the middle of an intersection, the second time on a highway (I was passenger, and yes, she has driven manual all her life). In both cases she was able to pull over in whatever gear it was stuck in, and come to a stalled stop.

The first time the dealer repaired it under warranty. They replaced the slave cylinder and the pressure plate, not sure what else they did.

The second time I had it towed to a Firestone repair shop: same diagnosis and same repair: Clutch slave kit and pressure plate. $500 in parts and $1,200 in labor.

Called Ford corporate hoping for some willingness to acknowledge that this was a problem, and to deal with it. They told me to tow it to a Ford dealer, otherwise I could pound sand. I have had truly awful experiences with the two dealers in my area. I had Firestone repair it.

Sounds like I am not the first to experience issues with the slave cylinder. Just want to:
1. put it out there
2. ask if anyone has ideas for ways to raise a bigger stink / get Ford to 'fess up and deal with it

Thanks
 


Intuit

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#35
Did they attempt to bleed first? (different vehicle) Had a cracked radiator that started out only sucking in air. (air is less dense than water) Maybe a few weeks later it finally started pushing fluid out. (crack gradually enlarged) Repeated "failures" lead me to wonder whether that system is allowing air to be sucked back in via one of the seals.

BTW on refill, these do us a thinner DOT 4 Low Viscosity fluid.
1606600483342.png
 


Messages
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Location
Laguna Beach, CA, USA
#36
Yes, on second failure at 45,000 miles I have given summarized version, longer version is:
1. pedal stuck to floor
2. I managed to drive it a few more miles by lifting clutch pedal with my foot
3. failed again
4. AAA came out, topped off the hydraulic fluid (with I believe DOT3)
5. drove fine for a few more miles, then same as step (2), managed to limp to where we were going
6. found a mobile mechanic who came out and bleeded the system
7. worked fine for a while, then back to step (2)
8. had it towed to repair shop
 




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