T-5 or T-56 Manual Trans swap

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dsteelejr

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Can it be easily identified externally? Idk which mine is because the 76 nova came with both factory and that’s the only reason I know it’s one

I don't know much about these rock crushers, except they are geared high because they are meant for cars, not trucks. You'd have to ask around or google it. I'm sorry I can't be of much help there.

Just curious, what did you mean in your previous post about being more streetable than a SM465? Other than not having OD, SM465 seems like a great pick up truck tranny. My '80 K25 has one and my uncle (a retired mechanic) has one in his '75 K20 and he says the SM465 is bullet proof. You'd have to run it out of oil to destroy it.
 

AuroraGirl

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I don't know much about these rock crushers, except they are geared high because they are meant for cars, not trucks. You'd have to ask around or google it. I'm sorry I can't be of much help there.

Just curious, what did you mean in your previous post about being more streetable than a SM465? Other than not having OD, SM465 seems like a great pick up truck tranny. My '80 K25 has one and my uncle (a retired mechanic) has one in his '75 K20 and he says the SM465 is bullet proof. You'd have to run it out of oil to destroy it.
the higher gearing and less bow rowing. one more street gear. for a more daily use in a half ton,. my 3/4 has a sm465 and it will keep it :) but i want a half ton 2wd in the future somehow maybe a 4wd and i like the idea of a manual
 

dsteelejr

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the higher gearing and less bow rowing. one more street gear. for a more daily use in a half ton,. my 3/4 has a sm465 and it will keep it :) but i want a half ton 2wd in the future somehow maybe a 4wd and i like the idea of a manual

The SM465 does seem like over kill for a 2wd half ton. GM also has some three speed manuals. I've never driven one. Maybe they'd be more streetable than a 465?

I built my K25 to be my work horse. Pulling, hauling, off-road so I love having that bullet proof 465 in it. To be fair, one minor annoyance is the fact that is slow shifting. Even though I didn't build it for speed it hauls ass and that slow shifting is a little bothersome when I'm having fun racing other **** boxes in town. I just keep reminding myself what I really built it up for. :)

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AuroraGirl

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Bu
The SM465 does seem like over kill for a 2wd half ton. GM also has some three speed manuals. I've never driven one. Maybe they'd be more streetable than a 465?

I built my K25 to be my work horse. Pulling, hauling, off-road so I love having that bullet proof 465 in it. To be fair, one minor annoyance is the fact that is slow shifting. Even though I didn't build it for speed it hauls ass and that slow shifting is a little bothersome when I'm having fun racing other **** boxes in town. I just keep reminding myself what I really built it up for. :)

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But four speeds :)

nice engine. You should get a factory air cleaner and snorkel
 

Donald

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I did a T56 in my 56 Chevy , you can us the stock aluminum bell housing and mechanical linkage . If you do you need a different clutch gear and through out bearing retainer , an adapter bell to trans and if you have a bench seat you will have to get a kit to move the shifter to the more forward shifter hole in the trans . If I were you I would go with a 5 speed , a lot less trouble and expense .
 

bucket

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Can it be easily identified externally? Idk which mine is because the 76 nova came with both factory and that’s the only reason I know it’s one

A '76 Nova would have come with a Saginaw 4-speed.
 

AuroraGirl

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A '76 Nova would have come with a Saginaw 4-speed.
thats not a saginaw?

okay i could have swore i crossed it by googling a cast# on the side and nova was written in sharpie which i thought meant it came in my grandparents 76 nova with a 250 that i have parts of. they said it was a manual so I guess i could just be running with a presumed fact. what would the saginaw be then

Found a photo, nevermind, it said Monza
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DavieL

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If you're thinking about going with a used T56, you would be better off getting a kit from Tremec.
I went through getting a used T56 for my 92 Z28 that was supposed to be good and had to have it repaired, and I could have gotten a new Tremec for not much more than what I have in the used one.
 

Ronno6

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Actually, I was incorrect on my tranny...it is a Muncie M-20 out of a 68 or so Vette
The ID is achieved by seeing how many grooves there are around the input shaft spline. Other than that, dunno. The M20 is a tad wider in range, but not much.

As for my choice of 4 or 5 speed, I want the feel of the 60's close-ratio, quick-shifting of a Muncie/Hurst combo. the truck manual trannies don't provide that feeling...
And, I really don't plan on doing much truck stuff with my C-10 beyond hailing my bicycle and maybe a few sticks of lumber.

I have happened on a potentially reasonable new, but out of warranty Tremec TKO 600.
It would work with my current bell housing/clutch setup. May need to shorten the ds a bit and relocate the shifter and floor opening.
I'm just wrestling with the cost vs. reward of the situation.
 

BrianCarroll

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Now in the process of installing a m21 where the sm465 was .I got a rebuilt trans for 1300 but now need the ring adaptor so I can use my truck bell housing. I have a 5.3 ls there were no ls with manual transmission if i got that right,
bell housing for sm465 is 5.125 id for main shaft hole m21 od of flange on front of trans is 4.685 so I need to buy the adaptor (advance adaptor) 29.99 that is all I need to get the trans to bolt up.This gives proper allignment.
But shifters are very expensive so looking for advice of what shifter works in my c-10
 

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