Shudder while taking off

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iamtherealJayy

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1978 Chevrolet K10 350/SM465/NP205. I’m going to start with saying this truck is my work truck and it has a utility bed on it mostly full of all my tools. The truck had an issue a while back where you literally could not take off in first it would shake so bad similar to a wheel hop feeling, so I started using low to take off. After a few weeks I couldn’t take off in low either. Replaced motor mounts(cooked lol) it’s somewhat better, I can take off in first if it’s perfectly level or down hill, but if there’s any resistance taking off it still shudders. Could this be some other mount somewhere? The transfer case looks solid nothing appears loose. Could this be in my clutch? There’s a loud obnoxious squealing noise while the pedal is pressed. I’m not positive where the engagement of the pedal needs to be since this is my only mechanical clutch truck(other is hydraulic) I currently have it adjusted to as close to the floor as possible since I prefer it to start moving when I start letting off(probably a good 2” off floor before it grabs) but it does grab almost all at once, there is nothing smooth about taking off in this truck. Will provide photos of anything requested.
 

bucket

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Clutch chatter. Plan on replacing the clutch, pressure plate, throw out bearing (likely the source of the squeal) and resurfacing the flywheel too. If the flywheel feels fairly smooth and doesn't have any terrible hot spots, you can get away with doing a "home resurface" using a **** wheel on an angle grinder or 80 Grit sandpaper on a DA sander. Well... that's only if using a quality clutch kit I should say. Some of the really cheap clutch kits have a tendency to chatter even on a brand new flywheel.
 

fast 99

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Noise when clutch depressed is likely the TO bearing, shutter would suspect there are hot spots on flywheel, disc is flat, or disc springs are broken / loose or oil on clutch.

Any of these could cause what you describe.

When new, clutch discs are wavy with high and low areas.
 

bucket

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Edit: W H I Z wheel...

Really?! We can't even say ****?! @HotRodPC there's another stupid one to remove from the list.
 

iamtherealJayy

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I wouldn’t doubt oil being on the flywheel, I really need to pull everything apart and reseal the engine/trans/tcase, they all leak. Inside the bell housing is disgusting(inspection plate missing and part has been cut off for some reason). Is there anything crazy or anything specific to watch for when changing a clutch? I figure it needs replaced this is my highest mileage truck lol it’s the only one with wear on the pedals.
 

Radiohead

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Might as well put an eyeball towards transmission/transfer case mounts too. They're most likely old too.
 

HotRodPC

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Edit: W H I Z wheel...

Really?! We can't even say ****?! @HotRodPC there's another stupid one to remove from the list.
What word is it? Figure out a way to get it to me. Surely it's not ****.
 

HotRodPC

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What word is it? Figure out a way to get it to me. Surely it's not ****.
sunuvbich it is WH1Z. I guess we'll have to use a 1 until I get on the home computer and get in there are change it. I thought I got most of those done, but I didn't make it to the W's yet. I think I made it to P or so or maybe even R. But when I get in there again....
 

fast 99

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I wouldn’t doubt oil being on the flywheel, I really need to pull everything apart and reseal the engine/trans/tcase, they all leak. Inside the bell housing is disgusting(inspection plate missing and part has been cut off for some reason). Is there anything crazy or anything specific to watch for when changing a clutch? I figure it needs replaced this is my highest mileage truck lol it’s the only one with wear on the pedals.
Front bearing retainer wear, fork wear, ect. Be sure to get the flywheel turned, bolt the pressure plate down evenly.
 

iamtherealJayy

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Since I know someone out there is curious,
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After having issues fitting a 12” clutch in my ls swap I decided to crack this clutch apart to find it’s an 11” clutch. Also there’s no pilot bushing in the crank. The pressure plate has some serious ripples on it and quite a bit of color towards the center
 

fast 99

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It's amazing sometimes what is found upon disassembly. Who would ever guess the pilot wasn't installed. Rust would also cause that problem.
 

iamtherealJayy

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Considering who I got the truck from nothing surprised me at this point. The bell housing bolts weren’t tight by any means I removed three by hand. The throw out bearing was also very past due
 

RecklessWOT

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Lol well holy cow that'll do it. Idk if dude was drunk and forgot, just didn't feel like doing it, or he tried and had a problem and just said "screw it, I'll slap it together and hope nobody notices".

I mean, on several occasions I have left the stainless steel hardware out of the caliper brackets and just let the pad kind of rattle around in there when changing brakes, they still work just fine except the pads wear quicker/unevenly. But never would I have thought to leave the pilot bearing out when changing a clutch, I mean you already came that far. Might want to take your wheels off and make sure there's bearings in your hubs and not just a ton of stacked up washers packed in grease lol

Jeez that's nuts. Glad you found it though
 

iamtherealJayy

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Well the people I got it from were some drunks in a trailer park… loads of questionable things. Not sure who did the clutch but it didn’t appear super worn but the flywheel and pressure plate had a lot of color. I’ve got the 5.3l in there now with brand new flywheel clutch pressure plate throw out bearing all of it. Get to do fuel system tomorrow.
 

SquareRoot

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Well the people I got it from were some drunks in a trailer park… loads of questionable things. Not sure who did the clutch but it didn’t appear super worn but the flywheel and pressure plate had a lot of color. I’ve got the 5.3l in there now with brand new flywheel clutch pressure plate throw out bearing all of it. Get to do fuel system tomorrow.
What's wrong with drunks in a trailer park?
 

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