Th350 behind 4.8ls

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AuroraGirl

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Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I rarely ever look at the indicator, I just go by feel. But I know some people hate when their indicator is broken.
again

this isnt a thing about it cant be done, im just saying it would be nice. youve never had a shifter that had wear and was loose/vague feeling? I feel like with how many old trucks you have had you probably have

If i had to guess its when the shift shaft bushing or whatever gets loose and things stack up
 

CountKrunk

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Count
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1984
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C20 Custom Deluxe 3+3
Engine Size
v8 350
Mine is broken i say the gears out loud as i pass em haha.
 

bucket

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again

this isnt a thing about it cant be done, im just saying it would be nice. youve never had a shifter that had wear and was loose/vague feeling? I feel like with how many old trucks you have had you probably have

If i had to guess its when the shift shaft bushing or whatever gets loose and things stack up

No ma'am, it's just second nature for me to do it by feel without even thinking about it. I've had a couple here and there with a wonky or out of adjustment shifter, but that drives me nuts and I fix it.
 

dirtscoots

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oregon
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joe
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77
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c10
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ls 4.8
It’s efi no carb. I’ve tried manually shifting and the outcome is the same.
Thank you for all the info.
 

AuroraGirl

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Engine Size
400(?), 350
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I now feel the need to ask what kinda things were done to make the th350 compatible here, because the issues you have may Just because the pCM is expecting a transmission signal of some kind and cant get it, so its assuming youre in limp home which means it cant reliably know what youre trying to do very well
 

xm20k

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David
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78
Truck Model
c10
Engine Size
388
The trans itself should still operate normally and not act as though it has a stall converter as it only needs rpm to turn the pump and vacuum for shift points.

Was the trans bought from a shop as a rebuilt unit or was it from a private seller that claimed "Recently rebuilt" but was possibly just power washed and spray painted? No disrespect but I've seen the later and if the engine is running as expected I'm thinking this trans needs to go to a shop to be gone through by someone that knows what they're doing.
 

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