Muncie transmission.

[Irishman999]

About 8 months ago on a different forum for gm diesels a guy told me some of our trucks came with a Muncie 4 speed, he said it was rare and he only saw one his entire life. Im pretty sure he also said if my truck had a Muncie reverse would be up and left.
My pops told me one time he thought almost all of the square body Chevrolets had a Muncie. I was just looking at some pictures of the Muncie SM465 and it looks exactly like the one in my truck as far as the case, right down to the panels you remove to install a PTO.
Does anyone know what the hell this dude was talking about? These Muncie's cant be that rare if i found 2 in the pic-n-pull the other day right?

 

[crazy4offroad]

The SM420 and SM465 are both Muncie transmissions, but Chevy also used Allison and Borg-Warner transmissions, as well as M-20, M-21 and M-22 "Rock Crusher" Muncie transmissions in high-performance cars. My guess is he was talking about the M-20/21/22 transmissions, since they had a shift pattern like that. Maybe pre-70's model 2WD or heavy duty trucks might have come equipped with the "Rock Crusher" trans.

 

[Irishman999]

The SM420 and SM465 are both Muncie transmissions, but Chevy also used Allison and Borg-Warner transmissions, as well as M-20, M-21 and M-22 "Rock Crusher" Muncie transmissions in high-performance cars. My guess is he was talking about the M-20/21/22 transmissions, since they had a shift pattern like that. Maybe pre-70's model 2WD or heavy duty trucks might have come equipped with the "Rock Crusher" trans.

Wow, thanks for the help. You dont happen to know the difference between the sm420 and 465 do you? Im hoping whatever that trans is i found at pic-n-pull will have the same splines as my current trans, everything else looks the same on the case.

 

[Manbearpig]

Gotta love that Muncie whine

 

[Irishman999]

Gotta love that Muncie whine

My Muncie quit whining and started crying, You can hear crap grinding and slamming around inside. It did not last long with low gear oil.

 

[87R10]

No way, these trucks came with Muncies?? I had no idea...what year(s) should I be looking for if I want to do a swap?? I really wanna ditch the TH350 for a manual

 

[Swims350]

we talking 2wd or 4wd here? a muncie car trans would bolt right in place of a short tail th350 or old three speed saginaw.

 

[Irishman999]

we talking 2wd or 4wd here? a muncie car trans would bolt right in place of a short tail th350 or old three speed saginaw.

Sorry i forgot to specify, Its 4 wheel drive.

 

[Swims350]

eh lol nevermind what I said then.

As other's said only one I know was stock was the sm465 or top loader 4 speed, granny gear 4 speed whatever you want to call it.

 

[GreaseDog]

probably a New Process A833... more commonly found in Chrysler vehicles, though used in GM trucks and vans for a time. it has no "granny gear" like other GM truck manuals, and 4th gear is an overdrive...

the A833 has the shift pattern you're talking about, and is indeed as rare as hen's teeth. i've literally looked at thousands of square body trucks, both road worthy and in the junkyards over the years, and have owned at least 20 myself. i have seen exactly ONE A833 equipped GM truck in person.

 

[Irishman999]

So this a-hole i was talking to got it backwards, totally ass backwards. They all came with the good transmission and the one odd ball is the non Muncie.

 

[burbdood]

So this a-hole i was talking to got it backwards, totally ass backwards. They all came with the good transmission and the one odd ball is the non Muncie.

Yep yep. My uncle in Reno has a stock 1960 Chevy Apache 10 with a Muncie 420 in it from the factory and I had an 86 K-10 4x4 with a Muncie 465 in it.

And if I remember right, the Muncie 420 and 465 had a non-synchronized 1st, (or granny) gear and reverse, and reverse was all the way right and down, while the M-20-21-22 had a synchronized 1st and reverse and reverse was all the way left and up.

 

[Irishman999]

Yep yep. My uncle in Reno has a stock 1960 Chevy Apache 10 with a Muncie 420 in it from the factory and I had an 86 K-10 4x4 with a Muncie 465 in it.

And if I remember right, the Muncie 420 and 465 had a non-synchronized 1st, (or granny) gear and reverse, and reverse was all the way right and down, while the M-20-21-22 had a synchronized 1st and reverse and reverse was all the way left and up.

You are correct sir, you are correct. I've been reading about it for a while now and it seems the SM 465 is pretty kick ass. They used these in 3/4, one ton and even two ton trucks.

If your ever back in Reno make contact burbdood.

 

[burbdood]

If your ever back in Reno make contact burbdood.

I'm hoping to make it back to Reno in February for a friends surprise b-day. If I'm able to make it, I will make contact fo' sho'.

 

[GreaseDog]

They used these in 3/4, one ton and even two ton trucks.

they used them in 1/2 tons too.