T56 problems- clutch or trans?

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cu440da

cu440da

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Not real knowledgeable on the manual transmissions. Needing some thoughts on what the issue is here.

At the track yesterday with my 5.7 hemi/T56 Warlock. On my shift into 2nd I heard a noise and the motor started revving. Limped it down track with what I thought was badly slipping clutch. Got to the pits to check things over. It barely moves before acting like it slips and makes all sorts of growly, snapping, popping noises. No noise in neutral, coasts just fine. Clutch in, no noise. Clutch out, sickening noise. Out of curiosity, we pushed the car by hand in gear to see if it would move and it did with some noise.

My first thought was the clutch is gone as it moves (slips)in gear. But I dont know enough about these to know is - that if the clutch were still good but the gear set is toast (or something else) if it would move with clutch engaged- like is happening.

Just trying to figure out if the trans is toast or the clutch.

TIA
 
cu440da said:
Not real knowledgeable on the manual transmissions. Needing some thoughts on what the issue is here.

At the track yesterday with my 5.7 hemi/T56 Warlock. On my shift into 2nd I heard a noise and the motor started revving. Limped it down track with what I thought was badly slipping clutch. Got to the pits to check things over. It barely moves before acting like it slips and makes all sorts of growly, snapping, popping noises. No noise in neutral, coasts just fine. Clutch in, no noise. Clutch out, sickening noise. Out of curiosity, we pushed the car by hand in gear to see if it would move and it did with some noise.

My first thought was the clutch is gone as it moves (slips)in gear. But I dont know enough about these to know is - that if the clutch were still good but the gear set is toast (or something else) if it would move with clutch engaged- like is happening.

Just trying to figure out if the trans is toast or the clutch.

TIA
Click to expand...
Are you using a hydraulic release bearing?
If clutch was slipping, I think you'd smell it!
I'd bet it's trans. drain oil and inspect for debris.
Hope I'm wrong!
 
Sounds to me like a stripped input gear. It happened to me once. But I suppose it could be a stripped 2nd gear. That happened to me too...... Or a broken shift fork. Yup, that happened to me too.......
In any case there's no getting around that the tranny needs to come down, and while it's out, you can inspect the clutch too, cuz you may have ripped the hub outta the disc; and yes that has happened to me too...I've been driving stick since 1969...so that's a lotta years to experience broken stuff.

If the engine was off and the tranny in neutral, and the clutch pedal up, while you were pushing it; and it was still noisy, I would guess the noise to be caused by something on the mainshaft, like a synchronizer assy or fork, cuz in this condition none of the geartrain is supposed to be moving.
But that doesn't explain how you were able to limp it back. That could only be explained by a clutch problem; like a finger failure. That has never happened to me.
So final guess, broken clutch.
 
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sccachallenger said:
Are you using a hydraulic release bearing?
Click to expand...
Yes, the factory Viper part.
Kind of off topic but, one thing that has always concerned me was the clutch master fluid turned black fairly quickly almost like it had burnt. Clutch release was immediate and at top of pedal travel. Before the install, I questioned American Powertrain about measuring release and shimming and was told it was not needed with the hydraulic release set up. I always had a suspicion the release bearing was not fully disengaged and was spinning when it wasnt supposed to and overheating the fluid.
 
cu440da said:
Y Before the install, I questioned American Powertrain about measuring release and shimming and was told it was not needed with the hydraulic release set up.
Click to expand...

This is totally false. You must measure. That's why they make shims. You have to make sure you have the proper clearance so the bearing fully disengages.
 
cu440da said:
Yes, the factory Viper part.
Kind of off topic but, one thing that has always concerned me was the clutch master fluid turned black fairly quickly almost like it had burnt. Clutch release was immediate and at top of pedal travel. Before the install, I questioned American Powertrain about measuring release and shimming and was told it was not needed with the hydraulic release set up. I always had a suspicion the release bearing was not fully disengaged and was spinning when it wasnt supposed to and overheating the fluid.
Click to expand...
The reason I asked, we had a Sebring for a few years and the slave or operating cylinder traveled too far and stuck the clutch fork in the released position.
In our case the car was stuck out of gear and had to be towed, so check this first! In our case, we had to change the master and operating cylinders.The Sebring was supposed to automatically adjust, which it did for the first 50k miles!
 
Got to agree with AJ on this one that it is the trans and needs to come out for some new parts.
(It could also be a stripped counter gear cluster. Or both second and the counter gear)
 
Just pulled the trans out. Input shaft looks fine, pressure plate fingers look normal. Need to pull the bell off yet to take the clutch apart for inspection, but nothing looked too scary so far. Damn, its looking like it might be internal hard parts.

20161004_162230.jpg
 
Looks like the clutch is toast! Pressure plate look pretty crazed and the flywheel doesnt look much better. There's a before and after pic of the clutch.

20150508_105508.jpg


20161004_185905.jpg


20161004_190021.jpg


20161004_190059.jpg
 
Jeepers, that's terrible!
I've got over 100,000 miles on my diaphragm and pressure plate,( It's on it's fourth disc tho) and it still engages really nice; So Ima guessing there's something wrong with that set-up.
 
Those puck type discs are hard as hell on flywheels. (heat fractures)
Your description of the symptoms you had at the track don't jive with that being the only problem.
Check the inside of that trans.
 
2500! Whoa! that sucker must have been slipping the whole way!Look at the pucks, they're almost gone. So in addition the checking the diaphragm very carefully, the release system needs a good going over.
 
AJ/FormS said:
2500! Whoa! that sucker must have been slipping the whole way!Look at the pucks, they're almost gone. So in addition the checking the diaphragm very carefully, the release system needs a good going over.
Click to expand...

Now I'm not accusing anyone of anything here, but someone that's slips the clutch excessively will have the same fast and hot wear.
I'm sure you know that puck style clutches are best for getting engaged ASAP.

Also note that the pucks are not wearing evenly, so apparently the pressure plate is engaging more on the outer edges of the disc.
This could be an indication of engine/trans misalignment. (could be)
 
AJ/FormS said:
Yeah I saw that odd wear too, but had no idea how that could occur, other than a warped PP.
Click to expand...

Seen it before and it was a factory mis machined bell where the trans wasn't inline with the crank.
It wore all around the edges of the disc and it looked almost new in the center.
 
That's why that type of disc materiel is junk. If you have enough plate load it will bust parts and go slow. If you try to control engagement, it kills the FW and PP. And the disc material will ball up and cause dragging.

It's great for a semi truck. Other than that............
 
An update.

Ordered a McLeod RXT twin disc and installed it. A bit overkill, but I can abuse it all I want and they say it will take it. Bellhousing dial indicated within specs, and is actually damn near perfect. Throwout bearing moves .440" like they say it should, and it has clearance to accomodate clutch wear. Everything looked good, so with the truck still on jack stands I threw it in gear to see if there were any funny noises. As I eased the clutch out I was watching the rear wheel to see if it engaged and as it did it wobbled a bit. Then it wobbled a whole lot. Long story short- I pulled the axle to inspect and found it was sheared clean off as it steps down to the spline diameter. Never thought that was gonna be the problem, but apparantly that was my issue at the track and I just happened upon the toasted clutch along the way.
20161108_190647.jpg
 
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