Clutch Problems
Thread Starter
5th Gear
Joined: Jun 2016
Posts: 5
Likes: 0
Clutch Problems
I picked up a '96 LT-4 6-Speed car with 120,000 miles last week.
Only problem I saw immediately was a grind going into first gear, which I originally attributed to a bad first gear synchro.
I've been driving it quite a bit and wringing it out when I get the opportunity. On the way home the other day I was at a light in gear with the clutch disengaged. After 10-15 seconds I started to feel the car jerk like it wanted to move. It subsequently stalled. When I pulled my foot off the pedal I had little to no pedal pressure but after a couple pumps it picked back up and I could get on my way. Next light, same thing.
Clutch fluid was low and dirty. Filled but the issue persisted.
I ordered a new Clutch Master and Slave Cylinder from Rock Auto and they came yesterday.
Am I going the right way with this? There's no slip on power and the only problem I really have in traffic is getting the car into first and reverse which, from what I've read, can be tacked up to the slave cylinder not engaging completely.
Only problem I saw immediately was a grind going into first gear, which I originally attributed to a bad first gear synchro.
I've been driving it quite a bit and wringing it out when I get the opportunity. On the way home the other day I was at a light in gear with the clutch disengaged. After 10-15 seconds I started to feel the car jerk like it wanted to move. It subsequently stalled. When I pulled my foot off the pedal I had little to no pedal pressure but after a couple pumps it picked back up and I could get on my way. Next light, same thing.
Clutch fluid was low and dirty. Filled but the issue persisted.
I ordered a new Clutch Master and Slave Cylinder from Rock Auto and they came yesterday.
Am I going the right way with this? There's no slip on power and the only problem I really have in traffic is getting the car into first and reverse which, from what I've read, can be tacked up to the slave cylinder not engaging completely.
Race Director
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
You're on the right path. Replace them both as a unit. This should take care of the problem...if not it was a necessary first step. Incidentally, Autozone will price match Rock Auto if you copy the page.
Thread Starter
5th Gear
Joined: Jun 2016
Posts: 5
Likes: 0
I found out on accident that whoever actually sold me the parts through Rock Auto has a warehouse 20 miles from my apartment so they delivered next day.
Regardless, thanks for the reassurance. I've heard the slave is a piece of cake once the cars in the air, but the master cylinder can be a bear because of some pin holding the arm to the pedal. Hopefully I can knock it out in a couple hours
Pro
Joined: Aug 2015
Posts: 656
Likes: 79
From: Jackson Wisconsin
Just did same on my 95. While its not that difficult it took 3 tries and its still not quite right. Here's my suggestions. When you install the slave to the transmission make sure the piston rod is in the fork socket. You probably can't see it but you can get you finger in there and guide it in. Make damn sure its in there or you will have trouble. Second, make absolutely sure you have bled the system. Bench bleed the master. I did not and am still suffering a bit of a problem getting into reverse, a sure sign there is a little air in the system. Otherwise it was smooth sailing. Oh yeh, getting the clip on the master under the dash was a classic bitch. I spend 3 days trying to get it on but once I found the system (I made a little tool) it was a snap. Good luck. By the way, 99% sure this is your problem.
Thread Starter
5th Gear
Joined: Jun 2016
Posts: 5
Likes: 0
Just did same on my 95. While its not that difficult it took 3 tries and its still not quite right. Here's my suggestions. When you install the slave to the transmission make sure the piston rod is in the fork socket. You probably can't see it but you can get you finger in there and guide it in. Make damn sure its in there or you will have trouble. Second, make absolutely sure you have bled the system. Bench bleed the master. I did not and am still suffering a bit of a problem getting into reverse, a sure sign there is a little air in the system. Otherwise it was smooth sailing. Oh yeh, getting the clip on the master under the dash was a classic bitch. I spend 3 days trying to get it on but once I found the system (I made a little tool) it was a snap. Good luck. By the way, 99% sure this is your problem.
I'm assuming once I get both pieces on I'll have to do a conventional bleed on the entire system too, right?
Pro
Joined: Aug 2015
Posts: 656
Likes: 79
From: Jackson Wisconsin
That's hard to say. It should be good to go if its installed correctly. The system is supposed to be "self purging" yet trapped bubbles are a big problem. I tried reverse bleeding, normal bleeding and a few other attempts and still have trouble with reverse. Maybe its the trans but forum guidance says to do the bleed again. Suggestions range from "pump the pedal 50 times"; "stand on it for 5 minutes and snap your foot off"; "step down, crack the screw, tighten the screw and let the pedal up slowly", and others. There seems to be no agreement. You may be lucky with suggestion 1. The authority on the clutch and trans for the M6 is ZF Doc. He seems to be the guru on these things. There may be others but he is The Man for all things ZF6. Fun car to drive, isn't it. I love to get it up to 60, drop to 3rd on the freeway and run it up a couple of gears. Fun fun fun til the trooper takes your license away( to paraphrase an old Beach Boys song.).
Thread Starter
5th Gear
Joined: Jun 2016
Posts: 5
Likes: 0
That's hard to say. It should be good to go if its installed correctly. The system is supposed to be "self purging" yet trapped bubbles are a big problem. I tried reverse bleeding, normal bleeding and a few other attempts and still have trouble with reverse. Maybe its the trans but forum guidance says to do the bleed again. Suggestions range from "pump the pedal 50 times"; "stand on it for 5 minutes and snap your foot off"; "step down, crack the screw, tighten the screw and let the pedal up slowly", and others. There seems to be no agreement. You may be lucky with suggestion 1. The authority on the clutch and trans for the M6 is ZF Doc. He seems to be the guru on these things. There may be others but he is The Man for all things ZF6. Fun car to drive, isn't it. I love to get it up to 60, drop to 3rd on the freeway and run it up a couple of gears. Fun fun fun til the trooper takes your license away( to paraphrase an old Beach Boys song.).
Pro
Joined: Aug 2015
Posts: 656
Likes: 79
From: Jackson Wisconsin
Make sure you get it right. I'm told that a mis adjusted clutch will cause premature wear on the ZD transmission. Mainlhy on the synchro's. Furthermore they are rumored to be expensive to repair. Used ones in good shape are made of "unobtainium".
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Le Mans Master
Joined: May 2005
Posts: 7,341
Likes: 2,272
From: Central Maryland
It's possible that simply bleeding what you have will solve the problem. In any case, park the car until you get it worked out, or you'll likely kill the synchronizers. The ZF is a tough gearbox, but it doesn't like being shifted without clutch disengagement.
Live well,
SJW
Live well,
SJW