furiousox

So this has been going on for a few weeks

It used to happen less and now more frequent

Basically at random times when I step into the clutch pedal to shift, sometimes the clutch pedal will have a bit of resistance, like it's stuck, and if I keep stepping on the pedal, it makes a "snap" and goes down normally. This usually happens once or twice in a row then the pedal is fine again

Needless to say this is pretty frustrating as I need to shift quite a bit in Southern California traffic

I did a quick search and only found a bunch of people with stuck clutch pedals, nothing like what I'm experiencing here

Any ideas? Is it the springs above the clutch pedal? Slave cylinder? Fork?

My car is an 08 with 80k miles

Dano523

Double check the clutch return spring at the pedal since it may be broken or on the way out (easy fix since it easy to get to under the dash), but if its that is not the problem and the clutch fluid is clean (ranger method if is dirty), then sounds like something inside the bell housing that is on the way out instead.

As for 80K and a bit of hard driving from the sounds of your quick clutching, might just be time for a new clutch assembly, including the slave cylinder as well.

There is no clutch fork, but instead a hydraulic slave cylinder with a throw out bearing on the end of it that pushes the clutch fingers inward to take the clutch disc plate pressure off flywheel plate when you press the pedal in. So here, it could be the throw out bearing worn out/fouling packed, or even the clutch fingers or plate that are worn out instead.

EtidW

When that happened to me it was the clutch return spring. I took it off and drove without a return spring until a new on arrived. Took about 3 weeks. The only job of the spring is to make depressing the clutch peddle and return of the peddle easier. It did no harm to drive without the spring.

icntdrv55

Disclaimer: I've never actually crawled under the dash to look at said spring; however….

I've seen a number of references by people about the clutch 'return' spring and it's purpose. Conceptually, if it's truly a return spring, it's purpose is to ensure the pedal returns to the fully extended position, but that would NOT make pushing the clutch in easier, but rather harder. If the spring's purpose is to make the pedal effort lower, it would be a clutch 'assist' spring. Right?

v26278

It's an over-center spring, at the start of the clutch pedal travel, it exerts pressure towards the driver to ensure the pedal returns all the way (this is necessary to allow the fluid in the master cylinder to properly drain back into the reservoir), around the mid-point (probably a little sooner) it starts to assist with moving the clutch away from the driver.

furiousox

Thanks for the help guys, I will remove the clutch return spring first and see if that fixes it. Hell I might like the clutch pedal without the return spring more lol. I will do some research and see if anything negative can happen from removing the return spring.

@Dano523 - thank you so much for the super detailed reply!

SUB VETTE

This is a good possibility. If it is broken you might consider replacing with a C5 spring which is less hefty than the C6 spring and makes controlling the clutch much smoother. I replaced mine on my 06 right after I bought it new, several years ago (even though it wasn't broken) and it made a big difference in smooth clutch engagement and significantly improved the driving experience.

furiousox

Yep looked under the dash and the return spring is broken on the left side

Hope my local dealer has one in stock...

Gonna take it off for now, if I can figure out how..

furiousox

So I took it outta the car within a minute, just had to pop off the one end that's left with a flat head

How the hell can a part made of metal break like this lol

Will get a replacement part and reinstall on my own...will research more on running without spring vs c5 vs c6 springs

Thanks to all who helped!

raspyc6

I cannot believe noone has said this...

Don't replace the clutch return spring. Leave the same out as it imparts a more linear feel to shifts. A Current member talked me into having it out and I do not regret it.

furiousox

Yeah it's funny because the car definitely feels better without the spring

However I read in a thread somewhere that without the spring the clutch pedal won't return to its proper height and that messes with some port in the slave cylinder?

Just don't want my already tired clutch assembly to have any issues sooner than it should lol

LPT2011

There is a reason they changed the spring in the C6.
I would never replace it with the C5 spring. Mine broke 3 months ago and it was still under my GMPP ('07). No quality service department would tell you to use the C5 spring

v26278

There is a GM bulletin advising against removal of the spring:

#PIP3821B: Removal Of The Clutch Over Center Spring - keywords cylinder hydraulic master pedal - (Apr 15, 2008)
Subject: Removal of the Clutch Over Center Spring

Models: 1997-2004 Chevrolet C5 Corvette
2005-2008 Chevrolet C6 Corvette
Equipped with a Manual Transmission

--------------------------------------------------------------------------------
This PI was superseded to update model years and tac notes. Please discard PIP3821A.
--------------------------------------------------------------------------------

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 recommended practice and customers should be advised of the implications of such an action.

Recommendation/Instructions:

The clutch master cylinder has a compensation port that is positioned within 1 MM of the top of the stroke. The compensation port allows internal pressure in the clutch hydraulic system to be exhausted into the master cylinder and also provides for system refill as the clutch disc wears.

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.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

weathermaker

I found it much easier to install the new spring with the clutch pedal depressed all the way to the floor.

SUB VETTE

Eight years of happy experience on a C5 spring is pretty good reliability for me as well as great clutch pedal control. No regrets here.

kellf190

The clutch spring on my C6 broke several years ago. I went to the dealer to buy another and the guy at the service desk said if it was him he would put the C5 spring in. He said lots of the C6 springs are breaking and he had not seen this with the C5 spring. I compared them side by side and there is very little difference.

My guess is the TSB was needed as many of the C6 springs were breaking, rather than people removing them.

furiousox

Interesting, thanks for the info guys. I found a 4-page thread on the issue of removing the return spring and bumped it for more feedback. I did see the GM bulletin, but also quite a few comments from non-believers

I ordered the spring from my dealer this morning anyways, still debating whether I should leave it out, as I do prefer the way it feels right now much more.

Dano523

Put the spring back in (either lighter tension c5 or C6 spring). If you have cruse control, then you need the spring back in the car for the system to work correctly (cruse control switch that kicks the system off when you press the clutch in, hence the spring holding the clutch pedal all the way out against the switch to hold it in so the cruse system works as intended).

furiousox

So just as an update

The spring arrived and I installed it.

A quick note - if you're doing it by yourself, FIRST figure out how to squeeze both of your arms to reach the clutch pedal, you will get everything done in 30 seconds as opposed to 15 minutes like I did. My shoulders wouldn't allow both of my arms to fit, and it was impossible to complete the job, until I REALLY squeezed both of my arms under the dash.

It's super easy to install - you compress the spring a little bit, put both ends into the holes, then press the clutch pedal all the way down, and hook the spring to the clutch pedal. That's it. The "hooking the spring to the clutch pedal" part is where an extra person or having another hand comes in VERY handy - you press the clutch pedal down with one hand, and hook the spring with the other. 30 seconds or less.

Anyways, my return spring must have been broken since I got the car 2 years ago, as I've never felt the clutch pedal this way. It honestly feels like I'm stepping the clutch pedal into mud as it's so soft, mushy, and returns so bloody slowly. I can still shift pretty quickly so not sure if this bothers me enough to want to remove the spring.

In fear of breaking stuff I will keep the spring there and adjust my driving habits to it accordingly, for now. Might rip it off again though as I really enjoyed the car much more without the return spring.

SUB VETTE

Now that you fixed the spring, check your clutch fluid and see if it is black. If so, perform "Ranger Method" fluid replacements until it's clean and you will get better pedal response feel.