98 6-Spd T/A - Clutch/Master-Slave Cylinder Problem

[Racr_X]

98 6-Spd WS6 T/A, 80K miles.

Clutch engagement point is very close to the floor. Clutch makes a sqeaky noise when depressed. When the car is cold, quick shifts on the 2-3 and 3-4 make a grinding noise when going into gear......... goes into gear every time. When bone cold, it even does it at low rpm, quick shifts only.

After driving the car for a little while and the car warms up and after using the clutch some too...... the grinding noise goes away and it shifts fine. I initially thought I had a synchro problem but since the noise goes away after using the clutch for a bit, I'm almost positive it's the slave or master cylinder issue.

Thoughts anyone? Do you have to pull the tranny to change out the slave cylinder. Seems like I've read about an adjustable slave cylinder rebuild kit. If I'm trying to save money, should I mess with the adjustable kit or just replace the slave cylinder(if that's the problem)?

[tabahr]

Re: 98 6-Spd T/A - Clutch/Master-Slave Cylinder Problem

Originally posted by Racr_X
98 6-Spd WS6 T/A, 80K miles.

Clutch engagement point is very close to the floor. Clutch makes a sqeaky noise when depressed. When the car is cold, quick shifts on the 2-3 and 3-4 make a grinding noise when going into gear......... goes into gear every time. When bone cold, it even does it at low rpm, quick shifts only.

After driving the car for a little while and the car warms up and after using the clutch some too...... the grinding noise goes away and it shifts fine. I initially thought I had a synchro problem but since the noise goes away after using the clutch for a bit, I'm almost positive it's the slave or master cylinder issue.

Thoughts anyone? Do you have to pull the tranny to change out the slave cylinder. Seems like I've read about an adjustable slave cylinder rebuild kit. If I'm trying to save money, should I mess with the adjustable kit or just replace the slave cylinder(if that's the problem)?

Clutch engagment should be right up close to the top. How old is your clutch? Is it shot? If you have to press the pedal all the way down to get a release, it is most likely not releasing all the way, causing the grinding.

Are you sure the problem is the slave cylinder? You can check for travel by removing the slave cylinder, placing a ball of clay behind the clutch fork, replacing the cylinder and working it. Then look at the clay and see how far it is dented.

I'm assuming the LS1 slave cylinder location is similar to that on the LT1. I could be wrong??

The LT1 slave cylinder is simple to remove. It is just 2 bolts on the driver side of the bell housing.

[Jeff_in_Atl]

If this clutch disk is worn out, it will release at the top not the bottom. For some reason, the pressure plate is not being pushed far enough for it to let go of the clutch disk. Possible problem could be the slave cylinder, bent release for, the mount for the fork bent or whatever the setup is, or the throw out bearing is worn making it smaller which makes no sense to me. Ok skip the last one. Being that is temperture related I would say it isn't a bent problem or it would do it all the time. I would say it is the slave cylinder since it can be effected by heat.

[M3EATER - GG '00 WS6 T/A]

The LS1 uses a combination hydraulic slave and throw-out bearing.

The slave bolts to the front of the trans, surrounding the input shaft and directly pushes the THB forward. No fork, no nothing.

Therefore, yes, the trans must be removed to access the slave.

I would first assume that you do have a hydraulic problem. Either the slave is leaking, the master is leaking or for some reason you have air in the system.

The poor pedal when it's really cold is a little normal. Mine is a bit funky at first in the cold & the parts are all fairly new.

These are a real to bleed. The bleeder sticks out the driver side of the rear of the bell housing ... barely. You can't really get a hose on it .... you can barely get a 1/4" drive socket on it .... shoot, you can barely touch it with your finger!

I can't attach a photo right now, but go to my web site and scroll down to the bottom of the home page ... the bleeder is the upper hex fitting shown.

http://www.provenperformanceconcepts.com

I would suggest a good bleed before you start replacing parts.

Gordon
PPC

[Jeff_in_Atl]

What he (Gordon) said. I need some sleep.

[tabahr]

Originally posted by Jeff 95 Z28
If this clutch disk is worn out, it will release at the top not the bottom

I need to get some sleep... obviousely that is correct., duh.

Given the way the LS1 slave cylinder is integral to the release bearing and located inside the bell housing, I'd say it is time to pull the trans, inspect everything and replace some parts.

[Injuneer]

The slave cylinder bleeding on the LS1 is difficult, but possible, and I would try it before pulling the trans. That would address the "air" issue. Check the level in the master cylinder reservoir..... that will tell you if there is a "leak" issue.

I don't think they changed the master cylinder design between the LT1 and the LS1, and when my car was still an M6, it was not unusual for the act of depressing the clutch pedal to randomly produce a "moan" from somewhere under the dash, and everything I ever read about it indicated it was just a "typical" LT1 clutch problem, and did not indicate a defect with the clutch.

As far as the impact of clutch wear on "release point", at least as perceived from within the passenger compartment, the hydraulic system essentially eliminates changes in pedal release height, by "filling" the system to take up the slack produce by clutch wear. Unlike a mechanical linkage, the hydraulic system is "self-adjusting" with regard to wear.