XavZ06

Hi everyone,

i'm sure clutch problems have been covered before and i have been reading a lot about them about worn pilot bearings and release bearings but from what i can gather i has various/different symptoms:

I have an 02 Z06 and here are the cars symptoms:

1) Since a couple of days i have a rattling noise coming from the gearbox when i have the clutch disengaged.
It only occurs with the clutch disengaged.
When i depress the pedal, the noise goes away.
It's especially noticable when the car is stone cold, then it sounds like a grinding noise.

2) The shifting is rather cluncky, when i release the pedal to quickly i get a 'clunk' coming from the gearbox area, like you're making bad shifts all the time.
When i release the pedal slowly and play with the throttle it works ok.

3) I did a high speed run 5th gear 150mph and the clutch pedal sank half way down after a couple of minutes. I depressed the pedal it and it came back up nicely afterwards.


Just for the record, my clutch fuild is clear, i followed rangers method and started changing it often to keep it clear. I did experience the pedal to the floor symptom 6 months ago.


Did anyone have these problems before?
Is my pilot bearing is on it's way out?
What would the next step be? New clutch?



Thanks, Xav

Eric D

Xav,

May have had these problems before, forum is full of them.

I doubt the pilot bearing, but my money would be on the through-out bearing on your slave cylinder.

How many miles on the currently installed clutch? Sounds like you might be on the right track with replacement.

XavZ06

Hi Erik

thanks for your reply.
the car only has 45Kmiles on the clock.

From what i've been reading the throwout bearing only makes noises with the clutch pedal depressed? Not sure tough.

Eric D

When bad they can make noise all the time, while depressed or not depressed. Most will make a rattle noise with clutch pedal up and the noise will go away while loaded with the pedal pushed in.

Carcass

You say it only does it with the clutch disengaged,but it quits when you depress the pedal?

When you depress the pedal is when the clutch is DISENGAGED,if the pedal is NOT depressed,the clutch is "engaged",it kind of sounds like you've got your terminology switched around.

A PILOT bearing will only make noise with the pedal depressed(clutch disengaged),while the throwout bearing may only make noise with your foot off the pedal at first,then progress to making noise all the time as the bearing gets worse.

What you're describing sounds more like torque tube bearings or couplers,but they won't necessarily cause "notchy" shifting

Whatever it is,it's going to involve the same amount of disassembly to fix it,so you've got a pretty good job ahead of you.

By "gearbox area" do you mean from the front area under the shifter?

Or do you mean the noise is coming from the rear,where the gearbox actually is?

XavZ06

Yes i have my terminology switched around, what i mean with the clutch disengaged is when i have the gearbox in neutral and pedal up.

never mind, this should make more sense:
- When the pedal is depressed or clutch engaged i don't have the noises.
- With the pedal up and the gearbox in neutral i get the rattling noise.

The sounds do apprear to be coming from around the gearbox area.

so it sounds more like the throuwout bearing then?

So you guys reckon i should inspect the torque tube as well?

XavZ06

I changed my clutch hydraulic fluid again theis weekend (it was slightly colored), and i have not been driving the car hard for a while and the noise has almost gone away now. I will probably take the car in to install a new clutch + hydraulics.


However, i still hear the cluncking when i release the clutch pedal quickly after taking the car out of gear. It also does it when i'm in a gear and when i let off the gas (in any gear)

The sound is a short 'clunk' and appears to be coming from the back of the engine/under the shifter. Anybody that knows what it might be?

I think this person has the same problem:
http://forums.corvetteforum.com/c5-g...er-noises.html

ipuig

If you have not done so, check the fluid level in the gear box. BTW you may already know this but the gear box is behind the torque tube in the rear of the car and the throwout bearing is in front of the torque tube inside of the bellhousing directly behind the pressure plate.

XavZ06

I found the gearbox already and the fluid level is fine.