ID Why My Clutch Started Slipping
#1
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Just looking to learn a little why my clutch started to slip and how to read a used clutch disk. To me it looks "glazed" but I also couldn't find any very good articles on what to look at with a used clutch.
FM level 1 clutch has 20k miles and started to slip in high gears no matter how I adjusted it.
![](https://farm2.staticflickr.com/1821/41728403410_c1c74273d8_b.jpg)
![](https://farm1.staticflickr.com/840/42819374354_24971e70cd_b.jpg)
![](https://farm1.staticflickr.com/939/43489006512_36c64e5c3a_b.jpg)
![](https://farm1.staticflickr.com/919/28649328607_50b9e9e65d_b.jpg)
FM level 1 clutch has 20k miles and started to slip in high gears no matter how I adjusted it.
![](https://farm2.staticflickr.com/1821/41728403410_c1c74273d8_b.jpg)
![](https://farm1.staticflickr.com/840/42819374354_24971e70cd_b.jpg)
![](https://farm1.staticflickr.com/939/43489006512_36c64e5c3a_b.jpg)
![](https://farm1.staticflickr.com/919/28649328607_50b9e9e65d_b.jpg)
![](https://farm2.staticflickr.com/1787/28649328697_aeb8e51e1b_b.jpg)
#3
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Sadly I sold the flywheel, however it was new FM so I hope it would have been within spec when it went in. Only ran a max of 14psi on a gt2560, that is when it started to slip but it should have been well within the power limit of the disc. The driving was 95% me so I dont think it was that.
#5
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No haha, carry on with the revisions! This happened before we started tuning, we started right when I got the fresh clutch in. I just finally got around to cleaning the garage and it reminded me to try to figure out what happened to this one.
Adjustment was in spec. I also replaced the master and slave with new oem to be sure. I tried adjusting it the FM supplied way and according to the FSM: both netting different engagment points but the same slipping and weak grab.
Adjustment was in spec. I also replaced the master and slave with new oem to be sure. I tried adjusting it the FM supplied way and according to the FSM: both netting different engagment points but the same slipping and weak grab.
#6
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I'm running a FM stage 1 clutch bolted to a 10lb Findenza flywheel and its hanging on to 18 psi and 300+ hp , just... I do think my step height is tighter than it should be though . I had to resort to extreme measures to get the clutch to fully disengage. I know I'm at the ragged edge of what it should be able to hold though. Fredb
#7
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Am I reading your pics correctly in that the flywheel side of the clutch is tapered? The inner half of your pressure plate looks heat/friction blued, yet it's the outside of the clutch friction material that's worn. Weird.
#8
Cpt. Slow
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You're really only looking at the final symptom, not the root cause. Clutch life can be significantly reduced by a lot of factors, like improper installation, too much grease/antiseize, misadjustment, poor driving habits, along with any leaks from your valve cover, cam angle sensor (or plug), rear main seal, oil pan, or input seal.
You can usually look at a flywheel or pressure plate to see a poorly machined piece, look for cracks in the friction disc for poor shifting or bad adjustment, but without the rest of the picture, I don't know how much you can say about that one.
You can usually look at a flywheel or pressure plate to see a poorly machined piece, look for cracks in the friction disc for poor shifting or bad adjustment, but without the rest of the picture, I don't know how much you can say about that one.
#10
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Hues- yes the side with the protrusion contacts the flywheel.
Curly- Thanks for that info, it was kind of what I was gathering as well. I was just hoping maybe something about the disc really stood out.
There are no oil leaks and all the associated seals and gaskets were replaced with OEM. I was very conservative with grease and only in the places where FM showed. Everything was assembled and torqued exactly how FM instructed.
Concealer- It did always seem to engage in the upper half of the pedals range of movement. There was still plenty of travel after engagement though.
Also to clarify: I'm not really upset with FM or looking to hold them accountable for the failure. Just looking to learn.
Curly- Thanks for that info, it was kind of what I was gathering as well. I was just hoping maybe something about the disc really stood out.
There are no oil leaks and all the associated seals and gaskets were replaced with OEM. I was very conservative with grease and only in the places where FM showed. Everything was assembled and torqued exactly how FM instructed.
Concealer- It did always seem to engage in the upper half of the pedals range of movement. There was still plenty of travel after engagement though.
Also to clarify: I'm not really upset with FM or looking to hold them accountable for the failure. Just looking to learn.
#15
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After you adjust the rod that goes into the MC to make 100% pedal= 100% engagement you will have basically turned the beginning part of the pedals travel into free play. Decrease the total pedal travel to get rid of excess free-play until you have free-play within spec.
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