Noise in transmission while clutch is engaged sm465

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dmac2590

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I have a whirling/grinding noise in my transmission while the clutch is out when I press the clutch pedal in its like magic and no noise. Its the sm465 4wd with I believe the np205 transfercase. I have a clutch kit including new fork and pivot ball to put in it. I'm just not sure that's going to solve my problem. I've read a few other forums about the input shaft bearing going bad but can't find it on any images anywhere. Any and all advice would be appreciated. Thank you all.
 

PrairieDrifter

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GebBuilt on youtube. Look him up. way better than a book being typed up here.

I would say bearings. The throwout bearing could possibly be the problem, they usually don't rattle when the clutch isnt being disengaged but I have had that happen before. I would inspect the throwout bearing first, it also could have spun on the fork.
 

dmac2590

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Dusterdude. Where is the input shaft bearing located in the transmission? All the diagrams I've looked at not one shows the input shaft bearing. Is it technically the mains gear bearing?
 

squaredeal91

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Input bearing probably. Big yellows is horrific and sounds like the titanic going down when starting out heavy lol. I've got a replacement to go in soonish.
 

dusterdude

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Its the bearing at the front of the trans,behind the throwout bearing
 

Cemack

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Like everyone has said it's either the throw out bearing or pilot bearing/bushing. I will attach a picture to show where the pilot bearing/ bushing is located
 

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pduffyd

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Looking at the sm465 trans, this is the input shaft, the bearing is behind the 4 bolt cover that the clutch release bearing slides on. That cover/retainer only goes on one way as there is an oil way in it to feed the bearing.
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I agree with prairiedrifter check out GebBuilt on youtube there is a 3pt video on a full rebuild of the SM465. Worth having a couple of beers while in front of the TV.
 

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