I have a 94 z28. about 4000 miles ago i had a bad chatter grinding vibration in my clutch pedal when fully depressed. As time went on it got worse. it sounds like something is making contact when its fully depressed. there is no noise when the clutch is released and the pedal vibrates just slightly.

I put a new clutch kit in it with a new fly wheel. i could not find anything wrong with any of the parts i took out. the vibrations had gone away until today they came back!!!! does anyone have ideas what this could be? possibly something wrong with the clutch fork?

 

what did your pilot bearing look like?

did you replace it when you did the clutch swap?

 

yes i did and it looked fine.

 

did you check if the clutch fork pivot retaining bolt was tight?

were there witness marks (scrape) on the outer edge of your old PP or the bolt heads of the PP show signs of contact on them?

 

i did not check pivot retaining bolt, and i did not see any marks. i only drove it for a day and did not try to let it happen. took off the slave cylinder today. fork seemed loose but i know it should have a little play in it. i guess ill have to drop the trans again. wasnt really looking forward to that.

 

so installed new clutch and was fine and now vibrations...

you could pull the slave and spacer from bell housing and look to see if the lip of the TO bearing is bending up.

still have to drop tranny anyway if it is.

TQ on PP bolts even all the way around?? @ 22 ft lbs.

I am thinking TO bearing is bad/bent or somehow not sitting right and not secured with the 3 tabs by the ring.

as you said droping the tranny most likely to see wtf is happening...been there.

 

Id go after the throwout bearing or springs on the clutch disc

 

yeah ive torqued everything to spec, probably just got a bad part from japan haha. which has happened to me before on a diff car. im gonna see if i have some time in the next few weeks to do it. i dont have access to a lift anymore so it should be fun

 

You know I get that somestimes on mine and I just found last night that my clutch pedal return spring is broken on one side so I think Im going to replace that before I do any more investigation.

 

So heres the update, I put the new spring in last night and the clutch pedal feels way better than before. I didnt feel anything yet on my 2 miles trek to work, I may go out for a cruise tonight so I can get a better feel for whats going on

 

Update: so I pulled the transmission and the lip on the throwout bearing was bent. Any ideas who sells a stronger one that won't bend?

 

supposedly SPEC now offers a "better" TO bearing for around $80. I don't know who they get them from

I use the "square" type that came with a SPEC clutch I had years ago. It just seems to have more meat on the bones but is also made....in China. Maybe this newer one I "heard" SPEC has availabe is better.