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T-56 Grinds when revving

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Old 02-14-2017, 07:42 PM
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Default T-56 Grinds when revving

2004 GTO.

Having an odd issue after replacing my tick master cylinder. Anytime I rev the motor with the clutch pushed in the transmission will grind. Doesn't matter what gear, it even does it with the car in neutral. Only thing I've noticed is that it starts to get a little worse when everything warms up. By worse, I mean it starts to do it at lower RPM's. It still runs and drives just fine, and I haven't had any issues shifting at WOT either. Just not sure what exactly would cause the problem. Possible the clutch still needs bled a little more? Thanks again in advance for any help.
Old 02-15-2017, 02:02 AM
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Could be a bad pilot bearing if it only does it when the clutch is pushed in. Might want to pull the trans before it wrecks the input shaft, if that's the problem.
Old 02-15-2017, 08:56 AM
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I replaced the pilot bearing with a new bushing when I had the trans out. Swapped out the lines and added a remote bleeder. I forgot to mention that when it does grind with the trans in neutral it will do it regardless of the clutch being in or out. Never had the issue prior to the master going bad and being replaced.
Old 02-15-2017, 04:06 PM
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Gave it a quick little drive to see exactly when it's doing it. It will grind only when the clutch is pressed, and roughly right about 4500-5k RPM, including in neutral. The pilot bushing is almost brand new. I'm starting to leave toward the clutch still needing bled a little more. Any other ideas that I could be missing?
Old 02-15-2017, 04:12 PM
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Sounds to me like either the pilot bushing or the throw out bearing. wont hurt to try bleeding it again but you might want to pull the trans to see whats going on.
Old 02-15-2017, 04:14 PM
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Have you jacked the rear tires off the ground and put it in gear and pushed the clutch in to see if the hydraulics are working correctly/disengaging clutch?
Old 02-15-2017, 11:33 PM
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I haven't. The idea being to try to spin the tires with the clutch in and make sure it's fully disengaging, I would assume?

Also wondering if it's possible if the shim is too big and causing issues.
Old 02-16-2017, 12:35 AM
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Yes on seeing if the clutch is disengaging.

What clutch do you have in the car? You added a shim?
Old 02-16-2017, 04:28 AM
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I highly doubt this has anything to do with your transmission. It sounds like something is wrong with the throwout bearing or something in that area, external to the transmission.
Old 02-17-2017, 12:44 AM
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Monster clutch in the car right now. We added a shim, but after checking over the post from Tick I believe we may have measured from the wrong point and added the shim when it wasn't needed. But, while it needs to come out, I can't imagine what would be making the grinding even with the shim in there.
Old 02-17-2017, 06:38 PM
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Maybe the throw out bearing took a dump? It will be good to pull the trans and look at that stuff? What monster clutch? I did the monster stage 2 in my car and my buddy's car and didn't use any shims.
Old 03-09-2017, 10:07 PM
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Update: Replaced the clutch last week with a McLeod RST. Everything went back in and the car ran great, minus some chatter from the clutch around 2k which I've come to find out the McLeod's are known for. Anyways, after a few hundred miles I noticed it started doing it again. Also, every so often, when going into third or fourth and letting the clutch out slowing it will start to grind. It continues to grind until I take it out of gear and then put it back in and release the clutch and it goes away. I'm starting to lean towards the slave cylinder going out, but I'm not sure because it's not constant. The slave that's in the car is only about a year old. Again, I'm aware that doesn't mean much with these.

I did notice driving the car today that it does not happen when the car is cold. Only after everything seems to warm up after anywhere from 8-10 miles, approx. The fluid in the master was also pretty black. Is there a possibility this could be an issue from the line getting too hot and boiling the fluid?
Old 03-10-2017, 04:24 AM
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So explain this correctly.

Car stationary, foot on the clutch and trans with any gear selected, you are saying the transmission makes a noise ?

Bare in mind with the above test, no parts in the transmission will be moving.
Old 03-10-2017, 09:18 AM
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Originally Posted by stevieturbo
So explain this correctly.

Car stationary, foot on the clutch and trans with any gear selected, you are saying the transmission makes a noise ?

Bare in mind with the above test, no parts in the transmission will be moving.
Correct. Only when you rev it, though. Roughly around 5k it will start to grind. Only with the clutch pressed.
Old 03-10-2017, 01:56 PM
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Originally Posted by G04T
Correct. Only when you rev it, though. Roughly around 5k it will start to grind. Only with the clutch pressed.
And once again I highlight the fact that during that test...Nothing in the transmission is moving. So I would struggle to believe the transmission is making the noise

It almost sounds like your release bearing is fucked, but you say you fitted a new clutch etc, so naturally you inspected and/or replaced this too ?
Old 03-10-2017, 03:55 PM
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Originally Posted by stevieturbo
And once again I highlight the fact that during that test...Nothing in the transmission is moving. So I would struggle to believe the transmission is making the noise

It almost sounds like your release bearing is fucked, but you say you fitted a new clutch etc, so naturally you inspected and/or replaced this too ?
This is what I was leaning towards, but uncertain because it only does it when the car is warm, which is what made me think it could be an issue with the fluid getting too hot.

The throwout bearing was inspected, but not replaced. It was less than a year old and didn't show any signs of failure, although I'm well aware that's not always the case.
Old 03-10-2017, 04:04 PM
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I've had internal slave cylinder systems do that on a couple cars, the clutch cover fingers were contacting the spring clip that retains the throwout bearing to the sleeve that travels on the input of the tranny. It typically happened one every thing got warm as well..
Old 03-10-2017, 05:30 PM
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Originally Posted by pdxmotorhead
I've had internal slave cylinder systems do that on a couple cars, the clutch cover fingers were contacting the spring clip that retains the throwout bearing to the sleeve that travels on the input of the tranny. It typically happened one every thing got warm as well..
So replacing the throwout bearing would resolve this issue?
Old 03-10-2017, 06:18 PM
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On mine it was the placement of the retainer,, it can go on 2 ways and of course I had it the wrong way.. Once,,,, the other time was a buddy.. we were like .... :doh:

Not sure if yours has the spring, mine had 2 L shaped ends that engaged holes in the bearing base, and then the coil sat to the drivers side when on correctly.. (T5 in a jeep...) so if you put it to the worn side the spring kinda ends up about 1/8 inch too far forward and when you push the cuts the fingers just tick the spring, and make an amazing amount of noise..

I jsut remembered, I also had one that was noisy because the clutch disk hub was a bit thick. It would rub on something inside the clutch cover.. (WAS on a VW... Bug 69.. )
Old 03-10-2017, 06:40 PM
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I'll look into that. I have a heat sleeve showing up tomorrow that I'm going to give a quick try just to see if I notice any difference. If that doesn't change anything then I'll just slide the trans back out and throw a new slave in it.


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