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Potential Clutch Issue? Lethal LPX-HD

15Oxford5oh

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Looking for feedback on my current setup as I am experiencing some complications and I'm wondering has anyone else experienced this as well.

Ben Calimer Built (Stg 3) MT82/ Lethal LPX-HD Clutch. Alum flywheel. Both brand new and installed along with other goodies last march, about 5 track passes on the setup.

I took the car to the track back in late Sept. after a pass I noticed when clutch pressed in that the car didn't want to let go of first gear, I didn't think much of it then till now. Now it's starting to do it daily driving, not wanting to let go of several gears unless I am double clutching it, and even then it may not let the gear go. Odd thing is when I am running the car hard I don't have any issues. But when I am normal driving seems like I am having a bunch of resistance when changing gears. Any idea? Is the clutch going bad already? It doesn't feel like it is slipping.
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NGOT8R

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Air in system? Try bleeding it again. Did you bench bleed the slave cylinder during install?
 
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15Oxford5oh

15Oxford5oh

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I imagine so, I actually had a very reputable shop do the install. And i asked then was the clutch properly bleed, they said yes that it was.
 

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I imagine so, I actually had a very reputable shop do the install. And i asked then was the clutch properly bleed, they said yes that it was.
Iā€™ve had my clutch line disconnected several times and had to pump the pedal literally a couple of thousand times. Iā€™ll be reinstalling my tranny in the coming weeks and have heard that if you donā€™t bench bleed the slave cylinder, youā€™ll always have air in the system, no matter how many times you pump the pedal. Have a look here to see the bench bleed procedure.

 
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15Oxford5oh

15Oxford5oh

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Looks like i'll be having to drop the trans again. So to your knowledge this sounds more like a slave cylinder issue rather than clutch?
 

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now you have me wondering. I have the same clutch but with a steel flywheel. I have no problems on the track but during daily driving I frequently (~10% of the time) I can't shift into (or out of) 1st or reverse. I have gotten used to coming to a full and complete stop, shifting from 1st and neutral back and forth several times before removing my foot off the clutch (like at a stop light). If there is resistance then I leave it in first and get a leg day work out why I wait for the light to turn green. Once I get moving then it shifts ok. I think that I need to adjust my shifter but haven't gotten around to it yet.
 

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Looks like i'll be having to drop the trans again. So to your knowledge this sounds more like a slave cylinder issue rather than clutch?
I donā€™t have a lot of experience in this area, but I am handling my own trans and clutch work. You said the clutch isnā€™t slipping, so thatā€™s what makes me think it could be the slave cylinder. Youā€™ll have a better idea if itā€™s the clutch if it looks burned and scorched. Did you replace your slave cylinder with the clutch change? When you made your passes at the track, did you slip it a lot?

I made 5 passes on my factory clutch and did detect slippage with just 6K miles on the car. My slave cylinder was also wobbly, so I bought a new one for the install and it too was wobbly out of the box, so apparently this is normal. When I pulled my clutch it was burned as seen in the pics. In addition, hereā€™s a short video of my factory slave cylinder. Iā€™ve always heard that itā€™s best to replace it when the tranny is out, whether or not you suspect it to be going bad, as itā€˜s a lot of rework to go back and do it later.



100029F6-D2F3-4B8F-AA87-551C51C98B4A.jpeg


51C85729-121B-4E53-95DA-00933996ACBF.jpeg

1669913242585.jpeg
 
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15Oxford5oh

15Oxford5oh

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now you have me wondering. I have the same clutch but with a steel flywheel. I have no problems on the track but during daily driving I frequently (~10% of the time) I can't shift into (or out of) 1st or reverse. I have gotten used to coming to a full and complete stop, shifting from 1st and neutral back and forth several times before removing my foot off the clutch (like at a stop light). If there is resistance then I leave it in first and get a leg day work out why I wait for the light to turn green. Once I get moving then it shifts ok. I think that I need to adjust my shifter but haven't gotten around to it yet.

Yea my only and biggest hesitation is that I do not want a potentially bad clutch to start wearing on a brand new transmission... I can deal with it not wanting to release the gear if it's just how this clutch is operating but again this is not normal so I want to take care of the culprit before it starts eating at parts..
 
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15Oxford5oh

15Oxford5oh

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I donā€™t have a lot of experience in this area, but I am handling my own trans and clutch work. You said the clutch isnā€™t slipping, so thatā€™s what makes me think it could be the slave cylinder. Youā€™ll have a better idea if itā€™s the clutch if it looks burned and scorched. Did you replace your slave cylinder with the clutch change? When you made your passes at the track, did you slip it a lot?

I made 5 passes on my factory clutch and did detect slippage with just 6K miles on the car. My slave cylinder was also wobbly, so I bought a new one for the install and it too was wobbly out of the box, so apparently this is normal. When I pulled my clutch it was burned as seen in the pics. In addition, hereā€™s a short video of my factory slave cylinder. Iā€™ve always heard that itā€™s best to replace it when the tranny is out, whether or not you suspect it to be going bad, as itā€˜s a lot of rework to go back and do it later.



100029F6-D2F3-4B8F-AA87-551C51C98B4A.jpeg


51C85729-121B-4E53-95DA-00933996ACBF.jpeg

1669913242585.jpeg

I replaced the entire setup when I changed clutch and trans, including slave cylinder. When I ran it at the track it was somewhat of a slip at 3800-4000 but not once did i smell clutch so i imagine it barely slipped to begin with.
 

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Could be air in the line (which is compressing instead of transferring the max travel distance of the throwout bearing) or if the bearing is either wrong or not spaced properly. Doubtful it's the wrong bearing, but sometimes when people swap clutches and such, some of them need spacer and some don't, the OE GT500 (last gen) style TOB is different than the GT bearing.

I'd thoroughly check the hydraulic lines and bleed it again, if it still persists, then the TOB isn't pushing into the fingers far enough and consequently they're not lifting it off the pressure plate enough so it's still grabbing. In turn, when you try to shift, the synchros are struggling because the input shaft isn't fully disengaged so they're trying to speed the two gears and the drive is still partially under force. in 100% effect it's like trying to shift without depressing the clutch, the synchros just aren't capable of that drastic of a speed/force difference.
 
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15Oxford5oh

15Oxford5oh

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Could be air in the line (which is compressing instead of transferring the max travel distance of the throwout bearing) or if the bearing is either wrong or not spaced properly. Doubtful it's the wrong bearing, but sometimes when people swap clutches and such, some of them need spacer and some don't, the OE GT500 (last gen) style TOB is different than the GT bearing.

I'd thoroughly check the hydraulic lines and bleed it again, if it still persists, then the TOB isn't pushing into the fingers far enough and consequently they're not lifting it off the pressure plate enough so it's still grabbing. In turn, when you try to shift, the synchros are struggling because the input shaft isn't fully disengaged so they're trying to speed the two gears and the drive is still partially under force. in 100% effect it's like trying to shift without depressing the clutch, the synchros just aren't capable of that drastic of a speed/force difference.

I'll rebleed the lines and go from there, but if what you are saying to be true why is it I do not have an issue with WOT driving and speed/powershifting it fine... Yet normal driving is total opposite? Wouldn't the synchros struggle even more under load?
 

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Could be air in the line (which is compressing instead of transferring the max travel distance of the throwout bearing) or if the bearing is either wrong or not spaced properly. Doubtful it's the wrong bearing, but sometimes when people swap clutches and such, some of them need spacer and some don't, the OE GT500 (last gen) style TOB is different than the GT bearing.

I'd thoroughly check the hydraulic lines and bleed it again, if it still persists, then the TOB isn't pushing into the fingers far enough and consequently they're not lifting it off the pressure plate enough so it's still grabbing. In turn, when you try to shift, the synchros are struggling because the input shaft isn't fully disengaged so they're trying to speed the two gears and the drive is still partially under force. in 100% effect it's like trying to shift without depressing the clutch, the synchros just aren't capable of that drastic of a speed/force difference.
Great explanation!
 

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Great explanation!
Forgot to add that there could be some sort of expansion in the system that's not allowing the TOB to get it's full range. This is where guys recommend the steel braided line.

Also, did you put fresh hydraulic fluid in it? Over time if it's exposed to the air, it can get moisture contaminated and that can also kinda mask itself as air in the system.
 
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15Oxford5oh

15Oxford5oh

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Forgot to add that there could be some sort of expansion in the system that's not allowing the TOB to get it's full range. This is where guys recommend the steel braided line.

Also, did you put fresh hydraulic fluid in it? Over time if it's exposed to the air, it can get moisture contaminated and that can also kinda mask itself as air in the system.
Fluid is still the same, I'll change fluid and what's what with rebleeding the system.
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