I have a 1996 convertable LT4/GS with a 6 speed. Whenever the clutch pedal is depressed fully there is a very loud rattle from under the car and a vibration in the clutch pedal. It seems most noticable when stationary and from 2nd to 3rd. The car doesn't do it when the clutch is depressed only partially and it shifts fine but as soon as you push the clutch pedal down all the way there's that rattle. We have replaced the Hydraulic clutch and throw-out bearing and it still does this. We thought maybe we were missing a spacer at the back end of the pedal assembly perhaps. Has anyone heard of this? Any possible hints would be greatly appreciated.

 

Strange....How many miles on it?

 

There are 58,000 original miles on the car.

 

Sounds like the clutch is over-centering at full depression. How did the fingers on the pressure plate look? Were there any rubbing marks on the clutch fork where it may have been contacting the pressure plate cover?

Chuck

 

Did you mean you changed the hydraulic clutch slave unit? If so is it possible you got a defective one (I had two defective units when I changed my original leaking one)? Or did you have the noise with the original hydraulic slave?

 

Yes the slave unit was replaced but it started doing this on the original. It all started when the transmission was looked at by a service shop. The pressure plate actually looked immaculate when we had everything apart, that's what is so frustrating.

 

Well, sounds kinda familur. Mine started making noises when I depressed clutch all the way, especially when I went to start. So I depressed just enough to change gears or start withtout making the noise. I suspected it was the throwout bearing. It got worse so I decided to do a clutch changout.
Went thru and changed out clutch disc, plate, bearing and pilot. Put it al back together and wham, engine wouldn't even turn over when I went to start. After several attempts, had starter tested, battery, etc, still same problem. I could however turn engine by hand. So I bit the bullet and pulled it back down. Guess what (I'm a dummy). The stud for the cluth fork had backed out a few trurns, causing the fork to hit the pressure plate when clutch was fully depressed. It has a locking device that had basically broken off and that piece was sittting up in a cavity on the front of the tranny. Of course, during the attempst to start, cluth fork had chewed the back of the pressure plate about 3/4 of rotation. Replaced it again, since these are balaned units.
So basiacally, original proble was the fork starting to hit old pressure plate, although throw out bearing was a little rough sounding (plate and disc seemed fine, 92K miles). Either way, tranny had to removed to fix it, and as we know, it seems half the car has to come apart to get it out.

 

Sounds like the clutch fork is out of position. My 92 does this also, but I rarely floor the clutch.

 

Mine does the same thing, ever since I had the clutch repleced. It made a lot of noise and got really bad before changing the clutch, because the fork had broken off! I am not sure why it makes the noise now, my mechanic looked it over right after the job and couldn't see anything. That was 10k miles ago, today it seems I lost all hydrolics in my clutch.
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