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Discussion Starter · #1 ·
Hey guys;

I have experienced what appears to be clutch slip when smoking the tires going into 3rd gear, the feel of the cars power changes and the pull seems to change, had faint clutch smell. 1st and 2nd pulls hard. Anyone else had this experience, if it was clutch slip, It should do it into 2nd. Any thoughts :-?
 

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Mark -

You didn't mention what active handling mode you were in. I very well could have an effect on the feel of the car when wheel slippage is felt. A couple of months ago, I drove a Justin Bell Z06 at Moroso Motorsports Park. The instructor that permitted me to drive it (It wasn't a school, just a "perk" drive for the business we do with them) but made me keep it in full active mode. Everytime I came around turn 10, it felt like I was getting fuel shut-off or starvation. He said it was just the active handling cutting in. Someone may have a better answer than I do.....Please speak up.

Steve Nix
 

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Mark Little said:
Hey guys;

Anyone else had this experience, if it was clutch slip, It should do it into 2nd. Any thoughts :-?
Not necessarily. It depends on how much torque is required to make it start sllipping. As a clutch starts to get weak, it will start slipping in the higher gears and as it gets worse and worse it will also start slipping in the lower gears.

The reason it may not slip in lower gears is becase of the torque muliplication of the transmission when in lower gears. In higher gears there is less mechanical advantage through the tranny, so the clutch has to actually transfer more force (torque) at the same HP levels. If the clutch was really weak, then in the lower gears the clutch will start slipping before the tires start slipping. In the higher gears, the tires will not slip (gearing too high), so the clutch becomes the first thing to slip if weak.
 

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It sounds like clutch slip to me.

:(
You have only had the car for a few months.
You don't get the slip in the lower gears because the tires are slipping (burning) before the pressure builds enough to get the clutch to slip/fail.
Tell us about your driving habits.
If you have been racing the hell out of your car, like you should be, then the clutch should be going bad along with brakes, rotors and other "wearing" parts.
No surprise.
But if you have been driving it like a old lady, we all might have a clutch problem.
Please give us more information and history on your car.
:cheers:
 

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Discussion Starter · #5 ·
Thanks for the feedback guys.
The Active Handling was off, my driving habits are not very radical, I get it out 2 to 3 times a week, maybe have boiled the tires 5 or 6 times, noticed the feeling into 3rd last two times, I have about 1,400 miles on it.
Maybe I should let the shop take a look at it, what do you think!

:-?

Thanks again!
 

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When mine exhibits odd symptoms, I ALWAYS have one or more picky Corvette owners drive the car and learn what they think. Quite often their views are decisive in diagnosing the issue.

If you wind up at the dealer, take your tech for a ride and demo the problem to him. If you just drop the car off, who knows what amount of flailing will be inflicted on your car.

Ranger
 

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Boiled the tires 5 or 6 times & 1,400 miles

I've been through many clutchs over the years and they all started acting exactly as you say yours is now. You have not used your car enough to go through a new clutch. No way. 1,400 miles and 50 burn-outs would not do it. The clutch is designed to go the distance. We all might have a problem here. I think you should get that baby into the shop immediately. It may never have been getting full pressure plate pressure. My first thought would be a defective pressure plate. Please let us know what happens. I'm sure the real gear heads here will have this figured out in a couple of hours. It's just a big stupid toy anyway.
Good Luck!
:cheers:
 

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Discussion Starter · #8 ·
I will keep you posted, I will give them a burn tomorrow and see what happens :D

I hope this is not the beginning of something!
:eek:
 

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This same subject came up on the board about 6 months ago where someone with new 02 started dong burnouts early on.

The response from C4C5specialist was that the clutch maynot be fully seated in yet, which would not let it grip fully (less surface area means less hookup on the clutch surfaces). He said he thought it might take as long as 5K miles to fully seat.

Is this something that you just notice, and on prior same burnouts found no problem/symtoms like you see now? If so, then yes, maybe something is wrong. If this is the first time you've noticed this, maybe your clutch plate has not fully seated in yet.

Of course once you have made it slip and burn a few times, it may not be 100% anymore :eek:. Maybe you should get some more miles on it and see what happens. You do have 3 years of warranty, but in reality GM may not even cover the clutch plate anyway -- wear and tear item :D.
 

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Clutch issues.

Hi there,
Yes, it may take as much as 5000 miles for a c5 clutch to correctly bed in to the pressure plate, and the flywheel.
As for why it is only slipping in 3, the answer is gearing.
As for the lower the number, numerically, of the given gear ratio, the more stress is induce to the clutch. The more torque multiplication that you give to a clutch, the less strain is put on it. The less multiplication, the more stress given to the clutch.
If you are burning up the tires, I would say that there will be substantial hot spots on the flywheel, and the pressure plate.
Honestly, I would expect that due to this, they would not cover this under warranty.
Besttoyou, c4c5:eek2:
 

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mark

1400 miles..........and 5 or 6 burnouts???.
I think this is MORE than reasonable...........
If the NEW & IMPROVED '02 clutch won't handle this, then somethings rotten in Denmark!!!!
Either you have REALLY balls to the walled the clutch.......which I doubt, since you have already SAID what you have done....................or Houston we got a problem.......
If I were in your shoes, I would fully expect this to be a warrantable item/problem............
c4c5, knows his stuff......................but, I would NOT be a happy camper in this scenario........THIS is what they were built for...................:(
Best of luck to you............:)
 

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WHAT?

I'm surprised by these responses -- "it's normal and not under warranty" in the same breath. I would not stand for anything like that. Is there a lemon law in your state? Break pads must be baked slowly, but not the clutch. It's ready to go out of the box. It's slipping or it's not slipping. The pressure plate is working or not working. The clutch and pressure plate are mated within two or three operations. I respect what these guys are saying, but, I don't buy it.

This same subject came up on the board about 6 months ago where someone with new 02 started dong burnouts early on.

Where is this guy today? I hope he didn't just start driving like an old lady to solve his problem. Can we dig this guy up and find out what happen.

:cheers:
 

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New design vs old design

Hi there,
The design of the c5 clutch is substantially different, as the pressure plate does not clamp in a straight line. It starts on the outside, and works its way inside.
If you look at a worn c5 clutch, you will find the highest wear marks on the outside edge. The reason for this is that as the clutch wears, the clamping for across the entire swept surface is more equal over the useful life of the clutch. Also, the fact that the fingers are adjustable, to compensate for wear that occurs.
With these facts presented, how can anyone expect the entire clamping force to be there, all at once??
I tell all my customers, this is the design, and I actually show them an old use assembly to illustrate my facts here.
This is not a conventional flat plate to flat flywheel type design, and in such, should not be confused. The clutch was designed for consistant high performance usage, not consistant tire spinning. Road racing, autocross, occasional drag strip useage and normal street driving are what this clutch was designed for.
Just the facts, so please understand this.
Besttoall, c4c5
 

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This is not a conventional flat plate to flat flywheel type design

So are you saying the assembly is designed to slip?
Can tire spin be pulled out of the equation?
Roll in 3rd gear and adding full power should make it slip bypassing the 1st and 2nd gear burn-outs.
 

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c4c5

news to me, and I'm sure a LOT of folks here...........makes me now think twice about dead stop starts........

Is there a different design that can replace this unit WHEN it goes bad??.
Or is this the way all replacments C5 clutches work?.

Must be a testimonial to how GOOD they really are........because a lot of guys on this forum have 100 or more 1/4 mile trips with the stock '01 clutch.........

I wish this was in the Owners manual as an insert especially for Z owners........it would save a lot of folks some big $$$$$.
c4, what is the approximate cost's, for a new '02 cluch, PP, & Flywheel installation??.

Thanks....... as usual Paul you are da' man!!!!GREAT info..............;)
 

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All of us have a healthy respect for the knowledge and experience of c4c5 Specialist. With that said there is also the ground truth that come from driving a Z06 and experiencing 100+ launches at the drag strip and many more than that in practice.

My own experience is that this is a strong clutch with a near stock motor.

The only issue I have had with my clutch is "cooked" clutch fluid that was heat induced and gave me the old "sticking pedal." Changing to high-temp fluid via a full bleeding of the hydraulics fixed that. I also intend to wrap my hydraulic lines as some other smart owners have done. Here is a link with a pic and info on the wrap used.

http://forums.corvetteforum.com/zerothread?id=212013

Scroll down to the post by Levrac68. Great info.

Chevy tech center disavowed the "cooked" clutch fluid explanation for the pedal issues and required my dealer to swap out the clutch. 90 drag launches (as of then) had produced no evidence of failure of any kind. They changed it out anyway and then the fun began, due to a botched install. That's a long story that I need not go into now. But I finally got the new clutch made right.

Three days later, I was back at the drags but now running BFG drag radials and going through the process of heating them and launch. Point is I didn't wait 500 miles much less 5000 miles.

Clutch is behaving quite normally, no slippage, no vibration, normal pedal feel.

After saying all that, I should also say that I don't smoke the clutch on launch; by that I mean I never dump the clutch at high rpm and make it slip freely, even by accident. That approach could lead to failure.

In sum, unless you are running an extra 50+ rwhp or dumping the clutch at high rpm, neither the 01 or 02 clutch should be slipping.

Ranger
 

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Stop riding the clutch, grandma.....:lol: :lol: :lol: :lol: No seriously you may have a problem. With 1400 miles on the tricker there is no way you should be needing a clutch!!!!
 

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Discussion Starter · #18 · (Edited)
Thanks for all the input.
I would have to disagree if warranty would not cover this if it was a problem, I do not abuse the car, I would consider what I have done up to this point as normal driving conditions, this is a z06, I would have paid much less and purchased a coupe or convertible if I just wanted a nice ride, however I went with the high performance model, this is how the car is marketed. I am not out dumping the clutch under high rpm, just enough rev, let the clutch out and roll on the throttle as the tires break loose. I do not do it often, however on the times I did, something felt different the last two times when I took it through 3rd gear and the smell was a slipping clutch odor, 1st and 2nd was fine :-?
C4C5 any way to inspect this if I put her up on a lift with out major disassembly.

Thank you all for your help! :cheers:
 

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Mark

In 3rd gear... did you feel the slip after you pulled your foot completely off the clutch, with the engine RPM "on the way up" to redline? Did you see, hear, and feel the RPM's "go up" fast without the associated forward motion?
We should confirm what you are feeling is clutch slip so we don't waste time chasing butterflies.
:cheers:
 

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Discussion Starter · #20 ·
Juan;

After I go into 3rd, clutch out, the torque starts going away, the tires stop pulling as hard (spinning) and the sound and feel is like the clutch is not letting the power flow to the tires, not tach out redline like total clutch failure would be. Just does not feel right, I do not want to try too many times, however if I have a problem I want it corrected.
You know what I mean ;)
 
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