Subject: Removal of the Clutch Over Center Spring - keywords cylinder hydraulic master pedal #PIP3821A - (06/16/2006)

Models: 1997-2004 Chevrolet C5 Corvette

2005-2007 Chevrolet C6 Corvette

Equipped with a Manual Transmission

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This PI has been revised to clarify model years and differentiate between C5 and C6. Please discard PIP3821.


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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
It appears that some Corvette owners are removing or disconnecting the clutch over center spring on their vehicles. This is not a good practice and we need to discourage it.

Recommendation/Instructions:
It appears that some Corvette owners are removing or disconnecting the clutch over center spring on their vehicles. This is not a good practice and we need to discourage it.

One purpose of the over center spring is to return the clutch pedal to the very top of the stroke to expose the compensation port. The second purpose of the spring is to provide for the designed clutch pedal feel.

Removing or disconnecting the spring may allow the clutch pedal to hang in an at rest position with the piston short of the compensation port. If the internal pressure is not exhausted the CSC may get stroked too far and a clutch hydraulic system failure may result.
The C5 clutch hydraulic systems were built by AP. The C6 systems were manufactured by FTE. Also, the pedal must be in the full up position, with the compensation port exposed, to bleed properly.

Anytime a dealer gets a hydraulic system complaint, the tech should inspect to insure that the spring is in place and properly connected. Related customer complaints might include poor shift performance, improper clutch release or transmission synchronizer damage.

That's good to know. I have read quite a few post of owners removing this spring.

Yea, par for the course is some wiseguy gets on some forum and tells people to yank parts out of the car and then later GM gets a rash of failures to find designed parts missing

I think their knees are too tired to push the clutch in from bending over waxing the car.

That is funny and possibly quite true

I have seen that many people have removed that spring

Dot see why someone would do that
the c6 clutch is verry lite as it is

What people should be paying attention to is how dirty the clutch fluid gets

Yes keeping fluid clean helps but still will not correct the problem that has existed since the 1997 C5.
In many cases it happens when racing and fluid get too hot. Also induces the problem is ill designed long tube headers that is now close to the clutch fluid hose heating up the fluid.
Try covering that hose with heat shield wrapping.

The pity though is that all someone has to do is simply post on some forum and say "do this" and no one questions what they read and before you know it thousands of Corvettes are screwed up due to stupid mod ideas.
Getting the spring off is easier then putting it back on.

I tested this for several months and put the spring back in which showed the spring is there for a good reason and taking it off can cause worse shifting patterns.

Is that the same spring as in the F-bodies?
Same function?
Same issues?

I don't have that spring and my tranny is actually shifting like crap. Every time I bleed the hydraulic system it gets better, but only for few months. There are no leaks and the parts looks fine to me.
Stock exhaust manifolds, stock clutch, stock hydraulics...

I am not certain but I do not think the F-body has this spring since the pedals housing design is much different for the F-body.
Best case is to look at the service manual

F-bodies have that spring.
Mine is just missing and I don't know if it's the cause of the troubles I'm experiencing.
Over here it costs something like $70 !! Don't ask me why, but in general we pay 3x the US price for car parts.
That's why I still don't have a new one...