1984 3 speed transmission

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Selo

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John
Truck Year
1984
Truck Model
C10
Engine Size
250
Gentlemen,

I have a 3 on the tree 1984 C10 with the original 250 inline 6. I bought it used in 1985. This truck is as basic as it gets. The only option installed was a step bumper.
The original 3 speed was replaced with what I think is an earlier model 3 speed (long story).
The current 3 speed is in need of a rebuild, but I'd rather rebuild and install the original transmission model. I am having difficulty determining the model 3 speed that would have been installed at the factory. I can't start looking for one until I know exactly what I'm looking for.
Any help will be appreciated.
 

Ricko1966

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Gentlemen,

I have a 3 on the tree 1984 C10 with the original 250 inline 6. I bought it used in 1985. This truck is as basic as it gets. The only option installed was a step bumper.
The original 3 speed was replaced with what I think is an earlier model 3 speed (long story).
The current 3 speed is in need of a rebuild, but I'd rather rebuild and install the original transmission model. I am having difficulty determining the model 3 speed that would have been installed at the factory. I can't start looking for one until I know exactly what I'm looking for.
Any help will be appreciated.
Should be a sticker on the glove box door that gives the RPO code for the transmission the truck was built with. Post it someone will tell you what transmission you need.
 

Keith Seymore

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Selo

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1984
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Engine Size
250
Gentleman, thank you for taking the time to respond with helpful info. Selo
 

Selo

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Engine Size
250
Hello again,

I am reviving this thread a bit. I have a different issue with the 3 speed. My truck is C10 2wd with 250 6cyl and 3 on the tree. Currently is rarely driven, but plan to drive it regularly.
The transmission was replaced back around 1997 with a GM 3 speed that I think is an earlier model trans. I just changed the diff. gear oil
and was planning to replace the 3 speed trans oil. I think the trans is some version of a Saginaw. I know that is a pretty safe guess! The issue is I can find the fill plug, but for the life of me can't find a drain plug. I figure its got to have one, but I can't find it. I feel like a d___b a__. Any of you fellows have any ideas? I plan to take pics to post tomorrow.

Cheers, Selo
 

Selo

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1984
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C10
Engine Size
250
Thought I'd give an update and beg for more info. The bottom right tail housing bolt was the charm. Once I knew where to look,
it seemed kind of obvious. Anyway, got her drained and refilled with synchromesh. Thanks again Turbo and others.

The trans work followed a service of the rear differential and an engine oil change. Next I'm going to replace the U-joints for safe measure.

I could not find a sticker with codes on the glove box. Only sticker there referred to Truck Camper Loading Information. I am sending pictures of the 3 speed trans. If I can't locate a trans of the type that was from factory I'll just keep this one. It obviously needs some seals. Its only problem is the synchronizer when down shifting from 3rd. Not hard to avoid that and when necessary, double clutching seems to help. I said I was going to beg for more info.....I'm including some pictures of the trans that possibly some of you fellows can help me ID it.

Cheers, Selo
 

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Selo

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Location
Greensboro nc
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John
Truck Year
1984
Truck Model
C10
Engine Size
250
Modified question....I know it is a Saginaw, but is it identifiable as an older version of the Saginaw 3 speed? Could this model have been OEM in my 1984 truck?

BTW, with new Valvoline Synchromesh oil in the trans., my synchronizer issue is gone!

Cheers, Selo
 

Old Guy Bill

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Those truck Saginaw 3sps were very desirable way back when circle track racing. A bunch of different version/gear ratios.
If I remember correctly we’d pull the cover and count some teeth, we wanted a 1:68 second gear?
 

bucket

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Modified question....I know it is a Saginaw, but is it identifiable as an older version of the Saginaw 3 speed? Could this model have been OEM in my 1984 truck?

BTW, with new Valvoline Synchromesh oil in the trans., my synchronizer issue is gone!

Cheers, Selo

Looks like there might be a date code? It's upside down. Too blurry for me to read though.
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