Manual Transmission Swap Options

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MN73GMC

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I have a little '73 short bed 2WD with a decent SBC crate engine and I'd like to swap in a manual transmission. Most of the information I've found on which transmissions would be good options pertain to 4WD trucks and mine is more of a sporty vehicle, not used for towing or mud bogging. I read great things about the Tremec TRX, but that's a healthy price tag, and the NV4500 seems like a good choice, but I can't tell if mine is a good application for it, or just the 4WD folks. There's the SM465, Saginaws, and I see Muncie 4sps in the area for reasonable prices, but I don't know if they would present serious installation problems. Any advice or links I missed where this has already been discussed are appreciated. Thanks.
 

Smtty58

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The SM465 came from the factory, so it's a bolt-in, once you gather all the parts. Others here will chime in with actual swaps, with pros ans cons.
 

Keith Seymore

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The SM465 came from the factory, so it's a bolt-in, once you gather all the parts. Others here will chime in with actual swaps, with pros ans cons.
It also has a granny gear, so not very sporty.

A four speed Saginaw should hold up to a mild 350 and can be had with varying different first gear ratios. Three speed Saginaws came in these trucks and are the same external dimensions.

K
 

goldpack

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I hope you can find one that is fun too. something that can feel great under foot and on the arm.
...such maybe a hard get,...but maybe someone here can say what makes a good thing a great joy.
(I have only had joy of making do... last gmc square I drove with a manual was a 1985 3500 trailer tower 4wd,...that needed double clutching with slow careful thought....big long stick with a gate that felt like a ponderous cavern....just helping a friend move his dad's horse hauler.....the opposite of a fun thing to be daily driving. )
 

bucket

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As a general rule of thumb, if you want a sporty transmission for a sporty truck, DO NOT get a transmission that was available in 3/4 ton and higher trucks.

I'm with Keith, a Saginaw 4-speed would be a good and affordable choice.
 

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You can use most all the parts from a salvage yard Chevy car 1960's through the 1970's and 1980's. Don't forget to get the engine flywheel and starter too. The only part that will need to be adjusted is the drive shaft.

You'll need the hanging pedal assembly from a truck. Buy an after market shifter and go.
 

Ricko1966

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Muncie 4speed and Saginaw 4 speed are the same diamension, bolt pattern, and tail shaft spline so another easy swap
 

MN73GMC

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Thanks for all the responses. Rebuilt Muncies seem fairly plentiful around here, so that might be my best option.
 

idahovette

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Depending on your rear AXLE ratio the Muncie may be a little steep in low gear? Not any worse than a Chevelle, Nova or Camaro, but the clutch action could be tricky. If you can find a low 1st gear Saginaw, that may be ideal. Or you can do it the way I do it in my Chevelle..........right foot down left foot up ;)
 

Ricko1966

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Thanks for all the responses. Rebuilt Muncies seem fairly plentiful around here, so that might be my best option.
You'll want an m20 an m21W or m22W. The w is important M20 was a factory wide ratio low 1st gear transmission and the one you would want factory. M21w M22w are aftermarket builds with different gears.
 

idahovette

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Yeah @Ricko1966 but you're talkin a lot of@$$$$$ when you for the "special" builds. Good condition Saginaws around here are 4-5 hundred, "good" Muncies are 800 to 1200 bucks,
 

Ricko1966

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Yeah @Ricko1966 but you're talkin a lot of@$$$$$ when you for the "special" builds. Good condition Saginaws around here are 4-5 hundred, "good" Muncies are 800 to 1200 bucks,
I was just letting him know the differences, since he's looking at muncies which he says are plentiful where he's at. I don't want to end up with an M21 or M22 and regret it.
 
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75gmck25

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GM also offered the A-833 overdrive manual transmission in some 81-86 trucks (MY06 code). I know almost nothing about it, but some did have a 3.09 low gear.

The A-833 was very durable as a standard 4 speed and was even used with big block Mopar engines, but maybe it lost some strength when the overdrive version came out.
 

Ricko1966

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There were a dozen versions of that transmission and the GM truck version is not tough like the Hemi Dodge version. The cast iron case one is tougher than the aluminum case one. If you get one be sure to get the bell housing and shifter, they are unique.
 

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