Manual Transmission T56 | T5 | MN12 | Clutches | Hydraulics | Shifters

Missed 3rd... now this???

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Old Mar 19, 2007 | 10:27 AM
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Default Missed 3rd... now this???

Missed a WOT 2-3 shift (Loud grinding!).

Now, the car won't move under power.

Symptoms:
Car running-
-----Press clutch, shifter in ANY gear, release clutch= NOTHING
-----I can row straight through all 6 gears and reverse without touching the clutch
-----When moving shifter through the gears, I hear a faint "cnch" sound between each gear

Car NOT running-
-----Shifter IN gear=car won't roll when pushed
-----Shifter in Neutral-car does roll when pushed

Centerforce Dual Friction, Stock T-56 tranny, stock shifter.

Thanks in advance for your net-diagnoses!
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Old Mar 19, 2007 | 10:38 AM
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trashed clutch
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Old Mar 19, 2007 | 11:21 AM
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Care to elaborate??? Is it the whole unit or just a pressure plate/disk/flywheel???

Could I get by with swapping the broken/trashed parts or should I swap the whole unit?
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Old Mar 19, 2007 | 12:03 PM
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If you can go through gears with the car running without using the clutch then it is slipping badly but not bad enough to let you push the car while its off and in gear. I suspect a trashed clutch disk. I would just drop the tranny and see whats broke in there.

I have a used stock clutch/flywheel up for sale if you need a cheap setup. It held fine and i was hitting a 150 shot, it didnt slip. I also have a slave too. I replaced it all when i did the engine swap. Lemme know if you need it.
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Old Mar 19, 2007 | 12:14 PM
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PM sent.

Thanks for the info!

Anybody else with a "worst case" scenario?
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Old Mar 19, 2007 | 04:10 PM
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Well, that's a good sign!
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Old Mar 20, 2007 | 10:03 AM
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OK, so one of our mechanics (with experience in performance and towing/recovery) says it's likely one of 2 things. I wanna see if you guys concur.

He says it's most likely the pressure plate is trashed. This is also the most frequent response I got on my local forum [PLUG] hsvracing.com [/PLUG].

He also believes it MAY be that the outer part of the clutch disk (with the friction material) has seperated from the inner hub.

I could see either one being the case. What do you guys think???
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Old Mar 20, 2007 | 10:11 AM
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Either can be the case. Either way you will liekly need a new clutch assembly.
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Old Mar 20, 2007 | 01:20 PM
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when you mis-shifted you hit 1st and it oversped the disc and it lost its segments.
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Old Mar 20, 2007 | 01:20 PM
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Either of these is possible. When you miss-shift you cause a few things to happen but the easiest explanation is to think of it as the clutch hitting a brick wall. Everything is spinning in one direction and then everything stops immediately. This can kill the plate and the disc. Once you get the assembly out of the car send me some pics and I will be happy to assist in trouble shooting. Thanks,
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Old Mar 20, 2007 | 02:16 PM
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Actually what happens when you mis-shift is that the car is driving the disc at the ratio you selected.If you hit first when it was correct for third you oversped the disc. That is ,the clutch is disengaged but the car is at speed that causes a disc overspeed. That disc speed can easily be much higher than the rev limiter of the engine. The good news would be that you never apply the clutch and take out the engine too.
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Old Mar 20, 2007 | 02:16 PM
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I can say this with a great deal of certainty. I DID NOT go back into first.

I'm not going to say "I don't mess up" but in my 7+ years in this car, I have YET to stick the shifter back into 1st (or from 3rd back into 2nd for that matter).

I just don't do it.

SPEC, I am fairly certain I am going with a SPEC clutch, are you associated with SPEC?
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