TH350 help

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jdogginit

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k10
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350
I have an 82 k10 SWB project I picked up. 350/TH350/NP208. Supposedly ran when parked right! Got the 350 engine running. Good compression. Put it in gear and nothing. No reverse or anything. It did roll a little bit in 2low but then nothing.

Fluid level was good, I thought, now I question that because The dipstick is the wrong one so I’m going to fix that. Pulled the pan. No chunks of anything but sealant. Filter was free. Fluid was red but dirty looking. Didn’t smell burnt. Disconnected torque converter from flex plate and spinning it spit fluid out the filter hole.

this is a lockup tranny th350c. The connection on the drivers side is not connected and there’s nothing to the plug inside (as seen in pics). I’m guessing someone tried to delete the lockup? Anyways I’m at a loss.

May pull it and try to rebuild but obviously if I don’t need to that would be cool.

Any help would be appreciated.
 

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PrairieDrifter

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Sounds mostly like a low fluid issue. I would get the proper dipstick. Check your level, if you need to add some then you should be home free pretty much. That's the first step.
 

jdogginit

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Sounds mostly like a low fluid issue. I would get the proper dipstick. Check your level, if you need to add some then you should be home free pretty much. That's the first step.
Yeah I’m gonna button it back up and add fluid. Thanks.
 

PrairieDrifter

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Yeah I’m gonna button it back up and add fluid. Thanks.
Generally reverse will be the first gear to lag or not work properly due to the fluid being low. Do that then go from there.
 

Ricko1966

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My opinion whe I've got the pan off I go with a deeper pan,with a drain plug, and a filter extension. I change 5qts of transmission fluid when I do my oil change,just me, but it makes sense to me to keep fresh oil in the transmission too.
 

Matt69olds

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With the pan off, the full mark on the dipstick should be about the same level as the oil pan rail.

It takes the application of 2 different clutch packs (the direct clutch and the low/reverse clutch to get reverse gear. It takes more fluid to apply 2 clutches, that’s why reverse is usually the problem gear.

If the pan is on and you haven’t verified the dipstick accuracy, pour in a couple extra quarts just to see what happens.

The 350 trans is one of the easier trans to learn to build. Very few special tools are needed, and those tools are easy to build. Definitely watch some YouTube videos, and have a service manual handy.
 
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jdogginit

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k10
Engine Size
350
Pan back on. I now know where the fill line is on the dipstick. Fluid topped Off and she’s driving! Lesson learned. But the pan gasket was leaking anyway. Now I need to fix the leak on the oil pan. Hahah
 

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