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Is it Clutch Time?

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Old Jan 13, 2010 | 08:19 AM
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Default Is it Clutch Time?

Never had to do a clutch, so I want to make sure these are the symptoms- the engagement point has moved way down- very close to the floor. I've changed the fluid a couple times, but that hasn't changed the point or feel.

The car is a 2001 with about 56k on it, with about 85 1/4mi passes on it- does this sound about right?

I'd be looking to go with the LS7 setup. I'd need a new disc, pressure plate, flywheel, slave, master, and bearing, correct?
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Old Jan 13, 2010 | 08:47 AM
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I may be getting ready to do the same thing, those parts sound about right. I'm probably going to got the spec route. I put some dr's on might and the clutch started slipping after a couple hard runs. I did the same thing and changed the fluid, however the weather has been bad here in Missouri for a few weeks and I haven't really had a chance to drive it. I going out for a drive today and then I'll make my decision on the clutch. Good luck.
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Old Jan 13, 2010 | 10:49 AM
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usually the clutch will start slipping some. but at 56k miles and drag racing you are probably due a clutch anyway.

Don't forget a remote bleeder
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Old Jan 13, 2010 | 04:52 PM
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The test for a bad clutch is put it in 5th or 6th gear and floor it, if the revs increase WITHOUT a corresponding increase in mph, your clutch is slipping and needs replaced.

There is also an inspection port you can remove and look at the clutch.
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Old Jan 14, 2010 | 08:51 AM
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Originally Posted by Oldvetter
The test for a bad clutch is put it in 5th or 6th gear and floor it, if the revs increase WITHOUT a corresponding increase in mph, your clutch is slipping and needs replaced.

There is also an inspection port you can remove and look at the clutch.
I don't get this type of slippage- what else could cause the moving engagement point?
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Old Jan 14, 2010 | 09:45 AM
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bad slave cylinder will cause that symptom - but results are the same - replacing clutch while you are in there to do the cylinder makes sense.
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Old Jan 14, 2010 | 10:38 AM
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whats yer mods/RWHP? If you are getting to the track with any regularity, I'd look at a beefier clutch, SPEC etc. I had an LS7 and it was fine, but when I added cubes I went to a SPEC.
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Old Jan 14, 2010 | 10:44 AM
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Originally Posted by Bull_in_a_china_shop
whats yer mods/RWHP? If you are getting to the track with any regularity, I'd look at a beefier clutch, SPEC etc. I had an LS7 and it was fine, but when I added cubes I went to a SPEC.
Not many mods- see sig. Don't have rwhp # though...
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Old Jan 14, 2010 | 10:51 AM
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You could buy a clutch made for the new C6. Find a used one with low miles. You'd still have to replace everything else, but it wouldn't be as bad on price. That's what I did and it runs great!
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Old Jan 14, 2010 | 02:59 PM
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I would think that the engagement point would mover FURTHER from the floor if the clutch was almost worn out. You said it is engaging CLOSER to the floor.
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Old Jan 14, 2010 | 09:36 PM
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Originally Posted by c5_4_me
I would think that the engagement point would mover FURTHER from the floor if the clutch was almost worn out. You said it is engaging CLOSER to the floor.
Well, if the clutch is worn then that means the cylinders would pump more hydraulic fluid into the pressure plate to compensate, forcing the clutch to engage. This would make me think that you'd have to press more on the clutch pedal to make it engage.
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Old Jan 14, 2010 | 09:52 PM
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Originally Posted by c5_4_me
I would think that the engagement point would mover FURTHER from the floor if the clutch was almost worn out. You said it is engaging CLOSER to the floor.
Mine grabs higher now than when i bought the car 6 yrs ago. Doing the 5th or 6th gear test is a good indicator. If it was me, id use it till it dies or if you have to drop the trans for some reason whichever comes first.

Im doing the Monster 2.5 series soon only because im dropping the tranny. My oem clutch still grabs perfect.

Last edited by Ikester; Jan 14, 2010 at 09:56 PM.
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Old Jan 14, 2010 | 10:02 PM
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I had my original clutch until 60k miles and it still had more left, but it just felt soft and did not grab in 5th and 6th. You could clearly tell the slipping. Why does the clutch pedal engage further away? Just wondering if anyone knows.
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Old Jan 14, 2010 | 10:13 PM
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My clutch is going, but it has not gone completely yet. Only slips under power in upper RPM area. Bad clutch chatter. Have a ACT twin disk on order. But yeah, if it is grabbing more towards he floor, then time for a slave replacement. Clutch might as well be done as well.
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Old Jan 14, 2010 | 11:01 PM
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I've always thought the clutch test was to slow down to around 25mph in 4th, thn floor it. If the rpms go up and the spedo doesn't, clutch is slipping. A couple of hard pulls from 3rd gear would also show clutch slipping. Good luck , hope its not the clutch
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Old Jan 15, 2010 | 07:31 AM
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Your symptoms seem wrong for a worn out clutch-the engagement point should be right at the top of pedal travel,not at the bottom,if it's a worn out clutch.
Sounds more like a slave cylinder problem to me too,but either way,the drivetrain's gotta come out to fix it,so you might as well replace all the clutch and hydraulic components while you're at it.
Be very careful when reinstalling the drivetrain-I found out the hard way that the pilot bearing is very easily destroyed,which means you get to do the whole job again.
I went with a Kevlar Composite pilot BUSHING(the second time) ,much harder to mess up if you're a clutz like me.

Be sure to install a remote bleeder-then when you change the clutch fluid,you change ALL of it,not just what's in the reservoir-and it only takes 2 minutes instead of 3 hours.
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Old Jan 15, 2010 | 02:11 PM
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Originally Posted by Carcass
Be very careful when reinstalling the drivetrain-I found out the hard way that the pilot bearing is very easily destroyed,which means you get to do the whole job again.
I went with a Kevlar Composite pilot BUSHING(the second time) ,much harder to mess up if you're a clutz like me.

Be sure to install a remote bleeder-then when you change the clutch fluid,you change ALL of it,not just what's in the reservoir-and it only takes 2 minutes instead of 3 hours.
Good advice, thanks for sharing. I know a clutch job is in my future, I just don't know when.
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Old Jan 30, 2010 | 06:53 PM
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I just bought this today, (I love it!) and I went out of town and ran it through the gears. The first time through the clutch seemed fine. The second time through, I went from 2nd to 5th and the clutch slipped.
Should I be concerned or just run it out?
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Old Jan 30, 2010 | 06:58 PM
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Originally Posted by C5 ChemE
I don't get this type of slippage- what else could cause the moving engagement point?
haven't read the thread--but i can tell you right now it's a bad slave cylinder. might as well replace the clutch while you have it apart.
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Old Jan 31, 2010 | 10:01 AM
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Originally Posted by C5 ChemE
Never had to do a clutch, so I want to make sure these are the symptoms- the engagement point has moved way down- very close to the floor. I've changed the fluid a couple times, but that hasn't changed the point or feel.

The car is a 2001 with about 56k on it, with about 85 1/4mi passes on it- does this sound about right?

I'd be looking to go with the LS7 setup. I'd need a new disc, pressure plate, flywheel, slave, master, and bearing, correct?
The engagement point will vary throughout the life of the clutch as the clutch disk wears down and gets thinner. The OEM LUK pressure plate compensates for this by self adjusting the diaphragm spring pivot point. The pressure plate spring pivot point can also be adjusted manually, there is a procedure for it in the service manual.
If the clutch does not slip and it is not exhibiting high RPM shifting problems I would continue to run it. The OEM LUK clutch is much better than what most give it credit for on this forum.
Get yourself a service manual, familiarize yourself with the clutch assembly and do not listen to the internet experts. Otherwise you may end up replacing a serviceable clutch with lots of potential life left in it.
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