4-speed manuals?

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LML Duramax 95 Z71

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Anyone know of a good 4-speed to put behind my 350 in my Z71? It needs to mate with my transfer case. I kinda like the idea of the old Muncie M20/22 Rock crushers because they have those strong straight cut gears. I heard that they can handle being in a truck and pulling trailers fine but I don't know about them mating to my NP241C transfer case. I'm not set on the muncies it's just an idea, I'm open to suggestions but I want fairly long gears. Also it needs to handle some power because my engine won't be stock for long, I'll be doing a cam, 4 barrel, intake, heads, distributor, all that good stuff.
 

RichLo

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Why not go with an NV4500?

There stock 1-ton manuals for these trucks so the swap would go pretty easy with off the shelf parts.
 

Chewy1576

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If you're stuck on a 4 speed, the SM465 came in the 88-91 2500 and 3500 400's.

The NP241C was behind the late SM465 with the hydraulic slave cylinder. The NV4500 is a 100% drop in replacement for the late SM465 also.
 

sewlow

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Only the M-22 is called a 'rock-crusher' as it's the only Muncie that has straight cut gears. They howl in every gear & makes sounds like other types of manuals that are in reverse.
Different case than the 20's & 21's. Stronger & heavier than the other Muncies.
M-21 & M-20's use the same case, but the '21' is a close ratio (Tall 1st gear, close ratios between gears) & the '20' is a wide ratio. (Low 1st gear, wider ratios between gears)
20's were equipped in GM vehicles with 3.55 & taller gear sets.
21's were in vehicles with 3.73's & shorter gear sets.
22's usually were installed behind high HP BBC's. They will work behind an SBC, though.
20's & 21's sound nothing like the 22's. They are virtually silent in comparison to that wonderful mechanical cacophony of noise that the 22 puts out.
A 22 behind a solid-lifter, header equipped, steep geared BBC, = goose bumps! Lol! Nothing else sounds like that!

You could also consider the Borg-Warner T-10 or the Super T-10 if you're really set on a 4 gear trans.
 

Justin S

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Only the M-22 is called a 'rock-crusher' as it's the only Muncie that has straight cut gears. They howl in every gear & makes sounds like other types of manuals that are in reverse.
Different case than the 20's & 21's. Stronger & heavier than the other Muncies.
M-21 & M-20's use the same case, but the '21' is a close ratio (Tall 1st gear, close ratios between gears) & the '20' is a wide ratio. (Low 1st gear, wider ratios between gears)
20's were equipped in GM vehicles with 3.55 & taller gear sets.
21's were in vehicles with 3.73's & shorter gear sets.
22's usually were installed behind high HP BBC's. They will work behind an SBC, though.
20's & 21's sound nothing like the 22's. They are virtually silent in comparison to that wonderful mechanical cacophony of noise that the 22 puts out.
A 22 behind a solid-lifter, header equipped, steep geared BBC, = goose bumps! Lol! Nothing else sounds like that!

You could also consider the Borg-Warner T-10 or the Super T-10 if you're really set on a 4 gear trans.
Well damn, I was all excited to throw out all of my Muncie knowledge but you beat me to it! :waytogo:
 

sewlow

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Well damn, I was all excited to throw out all of my Muncie knowledge but you beat me to it! :waytogo:
So was I. Glad I didn't. I would have looked like a real numb-nut. I think sewlow forgot more than I ever knew. Man that was close.

1978. 20 years old. Ridin' shotgun in my bud's '67 Camaro.
His Mom's car that she bought brand new. Originally an I.L.6/PG car. He's had it 5 years. He's 22.
It's on it's 7th motor since he's had it. Starting with a pretty mild 350/350hp/T350.
Each engine was progressively wilder. Not that he had broken the previous ones. It was just a need for speed!
By this time, a solid lifter Hillborn Injected (stacks & all!) 502/M-22 w/a V-Gate shifter, 4.88 geared, narrowed 12 bolt, (tuckin' M50-15's!(?) Ask your Dad! lol!) sub-frame connected, back 1/2'd car. Gutted interior, rubber floor, roll bar. Tin door panels. No back seat. Stereo? Hah! Dual exhaust! All the tunes you'd ever need!
Because of the umpteen different trannies & shifter's that had been in the car, the hole in the hump had morphed a few times & had become about 2' square.
At 60 mph, between having the header collectors right there on either side of the hole & the howl of that M-22, we'd have to yell, sitting right beside each other, to be heard over the noise.
Conversation was impossible!
Car didn't have a heater. Didn't need one with all that heat coming through the hole off of the headers!
What else could you do but smile?
And giggle like a school girl every time he ran it through the gears!
The car was still in his Mother's name until 25 years after it was given to him.
He still has it.
 

Ironhead

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Jeez! These kind of stories make me feel so old. I'm hoping all of us did this sort of stuff back in the day. I know I drove cars (wrecks, really) that were butchered, abused, and scared the crap out of people one generation older than me, and my friends did the same. The trouble is, the world has changed, changed too much. The "tuners' of today have to contend with emissions checks, safety stuff, and cars with zillions of miles of wiring, going to relays and computers.

When money was tight, we used the original six that came with the car, getting a friendly welder to split the exhaust manifold, and running duals through glasspacks. Didn't go fast, but sounded good. The guys with money had flathead V8s, or if they were lucky, an OHV V8 with a "three by the knee". Save your money and put on dual four-barrels--the car then ran like crap, but man, what bragging rights.

But now, I just try to keep my GMT 400 and mu Mustang GT running sweetly, drive way more carefully, and read these stories that take me back. Keep em coming.
 

LML Duramax 95 Z71

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Only the M-22 is called a 'rock-crusher' as it's the only Muncie that has straight cut gears. They howl in every gear & makes sounds like other types of manuals that are in reverse.
Different case than the 20's & 21's. Stronger & heavier than the other Muncies.
M-21 & M-20's use the same case, but the '21' is a close ratio (Tall 1st gear, close ratios between gears) & the '20' is a wide ratio. (Low 1st gear, wider ratios between gears)
20's were equipped in GM vehicles with 3.55 & taller gear sets.
21's were in vehicles with 3.73's & shorter gear sets.
22's usually were installed behind high HP BBC's. They will work behind an SBC, though.
20's & 21's sound nothing like the 22's. They are virtually silent in comparison to that wonderful mechanical cacophony of noise that the 22 puts out.
A 22 behind a solid-lifter, header equipped, steep geared BBC, = goose bumps! Lol! Nothing else sounds like that!

You could also consider the Borg-Warner T-10 or the Super T-10 if you're really set on a 4 gear trans.

Exactly. I know the M20 has a little gear noise so that's why I wouldn't be opposed to it. I would prefer a M22 though for sure. Would a M22 bolt straight up to my 350? As far as making the transfer case work I could just do a divorced setup with like a 2 inch driveshaft so I'm not that worried about that part. If a M22 will bolt straight up to my 350 then I definitely want to do that because it would work well with my 3.73s and I can get one for 750$ on eBay. Figure clutch stuff and a shifter, I'd be a little over a grand for a whole new setup with my favorite transmission. I'd call that a-ok :cheers:
 
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