Update on TH350

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j_dog00

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Ok guys,
First off I want to thank all of you for your knowledge, advice and otherwise responses to my posts, believe me they are all welcomed, I am a newb.
This is a conglomeration of former posts, as some of you know been having trouble with the th350 Auto. After changing the filter, gasket, vacuum module, torque converter to Flexplate bolts, and new fluid..I think I have it narrowed down.
The reason I even looked under there to start was because of a loud metallic knocking noise, coming from the TC area, truck shifted fine at this point.
Upon inspection, I found two bellhousing to engine block bolts loose, I tightened them and bam It ran ok for about an hour, and the metal knocking noise was gone..
then it started to act up..it would slip in low gears, almost not upshift at all, and downshifting would bog the truck down.
Then it stopped going into any gear period.
This is when I did all the work with the filter, vacuum module, fluids and so forth.

So my guess is, that the Torque Converter is not seated properly, also when I tighten the 3 TC to Flexplate bolts..the flexplate flexes a little bit to seat with the TC. Is that an issue? If it's seated properly I'm guessing it wouldn't flex unless necessary under stress of a running engine.

After research, money and headaches..I think that's it..so what's the easiest way to fix this,? Do I have to pull the tranny back? Is there a trick for this? I have two jacks, and no lift..thanks again guys!

Also, the gentlemen who said in an earlier post it is mt torque converter ears..you get to say I told you so! Thanks again

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Preston

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k10
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Jessie, I have found the easiest way is to remove the driveshaft, unbolt from rear and set aside try to keep both ends clean, wrap some tape around the rear u joint to keep the cups from falling out. Of course have the truck on jack stands with the wheels chocked, I use two pieces of all thread once you get the bolts out of the transmission on the sides put a nut on both sides of the block this will let you slide the transmission back without having to lower it, you should have a jack stand holding the rear of the transmission up take it slow and easy of course you need to take the lines to radiator and linkage loose before you start. Good luck be safe and stay intouch


(Please always have someone help you you can never have too much help, take it slow and easy stay safe)
 
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j_dog00

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Dillon, Montana
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Jesse
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1980
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C10
Engine Size
5.7l 350
Update..tranny is screwed..already bought a 350 auto and its going in tomorrow. Here's a pic of the truck

Now that crap is done..I need ideas on paint..trim..and otherwise cosmetics..I want to do things custom..post pics of your upgrades guys!!

I'm thinking square halo headlights..rollpan..new chrome trim..white rattle can paint job..whatever isn't to terribly expensive.

Will post engine pics tomorrow..it's a strong 350..4 barrel
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Frankenchevy

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Do you really do $20 dump runs? I wish you lived around here. I could keep you busy for a year!

Glad you got a plan together. Watch a few videos on seating converters, etc.

Good luck
 

TerryRH

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Do you really do $20 dump runs? I wish you lived around here. I could keep you busy for a year!

Glad you got a plan together. Watch a few videos on seating converters, etc.

Good luck
That's what I'm saying!
 

Matt69olds

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The all thread is a good idea, the best advice I can offer is to slowly tighten the bellhousing bolts a little at a time, and evenly, while making sure the converter will spin. If the converter locks solid, STOP! The converter isn’t seated in the pump. If you continue tightening the bolts, you will tear up the pump, and most likely the converter. Which brings up another point, don’t use the old converter with the new trans. Whatever debris in the old converter will be pumped into the new trans. Use some brake clean and compressed air to clean out the trans cooler, same thing, whatever debris that’s in the cooler will be pumped into the trans.
 

78C10BigTen

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When putting the converter in the trans you want to turn it and put light pressure against it, it should fall back in 3 times. 3 different clunks. So was the TC broken or was itt the trans all together? Btw im the guy that said about the broken ears.
 

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