Bad clutch or bad transmission???

[Mike93]

So I've been having difficulty shifting for the past few thousand miles. When I swapped the mtx into the car I went with a reman Autozone clutch...it was supposed to be a temporary clutch since I wasn't 100% confident the swap was going to work.

A few thousand miles into it and it shifted fine. At about 10000 miles of pretty light driving I noticed difficulty upshifting. If I was higher up into the rpms (above 4000ish) I could shift okay. But from say 2000-4000 it would take a few seconds to engage, I had to wait for the rpms to drop down to idle. At this time I noticed I was severely down on trans fluid so I filled that back up, figured I may have got the trans hot and toasted some synchros???

So I put in a trans from a friend that was in solid shifting condition...same problems with the shifts.

I have adjusted the cable several times, as well as replaced the clutch cable about 5000 miles ago.

It feels like when I push the cluth pedal it's not fully disengaging the clutch, but several clutch adjustments later and it still won't go. I'm beginning to wonder if the pressure plate is just getting weak and not allowing the clutch to function properly...seeing as this problem has occurred with two transmissions and I really don't drive this car all that hard.

Thoughts???

 

[1993MTXSHO]

its probably the clutch, those are symptoms of a bad clutch. Did you notice if the clutch had any broken straps or fingers when you reinstalled it?

 

[AREA 91]

Did you replace the TOB and quill sleve? Did you use green loctite on the quill? Did you use red loctite on the pressure plate bolts?

I think your next bet would be to pull the starter out, and use an inspection mirror to look at the pressure plate bolts. Also, use a feeler guage between the flywheel and pressure plate. There should be NO gap there. IF there is, you found the problem. There have been some stock valeo disc's as of late that are thicker than they should be, resulting in poor dis engagement. If the flywheel dowel's are too long, this will cause the same symptoms of hard shifting.

I just did a 3.2 swaqp im my 91 a few weeks ago, and I had to grind down the dowel pins on the flywheel, so the pressure plate would fit flush. I will always "trial fit" the flywheel/pressure plate from now on.

Hope this helps, and report back your findings.

 

[Mike93]

When I had reinstalled it I didn't notice any broken straps nor fingers. Clutch wear looked to be okay too.

I did replace the T.O. bearing and reused the quill sleeve as everything felt good. So no locktite on the quill since it never came off...and yes, I used red loctite on the pp bolts.

Depending on my motivation level I'll go in there with a feeler gauge...

I'm half tempted to just order up a CM1

Man, going from this car/clutch set up to my Mustang with a Spec 2 in it...makes me hate driving the SHO!!!

 

[dantheman68]

what kind of fluid is in there?

try shifting with the car off, and foot off the clutch pedal... if it goes smoothly, your synchros are not the culprit... however if the fluid fixes nothing, this sounds like a clutch

 

[Mike93]

what kind of fluid is in there?

try shifting with the car off, and foot off the clutch pedal... if it goes smoothly, your synchros are not the culprit... however if the fluid fixes nothing, this sounds like a clutch

GM syncromesh, noticed no difference between this and the sheap atx fluid that was in there before. I keep forgetting to shift with the car off...I'll post back next time I'm in the car.

 

[Mike93]

Engine off...car in neutral...shifts fine. Clutch in...still shifts fine. Thoughts???

 

[93rev2sev]

How does clutch engagement from a stop feel?

The thing that sticks out to me is that:
It FEELS like it's not disengaging..

Try this: Engine running, from neutral, at a stop, press clutch pedal to floor, shift to first. Pull the shifter slowly out of first, but not into neutral. Use a feather light touch to push the shifter back into first. If the input shaft has begun to spin(read: clutch is not fully disengaged), you will feel the synchros attempt to engage and it will grind. There is a spot that is just out of first but not quite into neutral that will allow the 2 sides of the synchro to spin at different speeds AND not lock out the gear. To find that spot might take practice Let up on the clutch pedal enough to get the car to BARELY CREEP. Keep your foot there and pull out of gear into neutral. You will feel the synchros let go. Go NO further. Thats the spot. Return the selector to neutral, stop the engine, let up on the clutch pedal and start over from square one but this time, leave the clutch pedal pinned to the floor.

I'm not saying that the input shaft will always be at a dead stop with your clutch pedal to the floor...even in a 'normal' system, but the amount that it spins can be felt in the grinding that I mentioned above. If you DO get grinding, it should stop very quickly.

Keep in mind that you will potentially be grinding on your first gear synchro. To limit the grinding, come out of first and go right back in before the input shaft has a chance to get to 900RPM. If you find the input shaft is immidiately starting to spin when the cars inertia is removed, then you have diagnosed a disengagement problem.

Don't try this until we see how bad I get flamed!

 

[Mike93]

How does clutch engagement from a stop feel?

From a stop the clutch grabs fine...only issues I have are upshifting. Most of the time it feels like I have to push the last 10% of the throw to engage the gear. No grinding...just annoying.

 

[93rev2sev]

If you can shift by rev matching and not using the clutch, your tranny is fine and your clutch is sticking.

 

[Mike93]

If you can shift by rev matching and not using the clutch, your tranny is fine and your clutch is sticking.

That I can do with no problem...