3 on the tree question
 

Is the original 3 speed a saginaw?

Re: 3 on the tree question
 

Depends what year.

Re: 3 on the tree question
 

72 2wd

Re: 3 on the tree question
 

Also depends on the motor is my understanding. Believe 350 and bigger was the Muncie. What does the SPID say for transmission.

Re: 3 on the tree question
 

Doesn't say anything about the transmission. But the motor says 350

Re: 3 on the tree question
 

If you have the 350 it is my understanding then that it should be the HD 3 speed which is the Muncie. I’ll look something up real quick.

Re: 3 on the tree question
 

So I am not sure here, previous information I had showed that 350 had a H.D transmission. The attached screen shot shows that may not be true for 1972. This is from the 1972 spec book care of the GM Heritage Center truck books. I’ll post it and see what you think,

Re: 3 on the tree question
 

And from the 1971 spec book (what mine is) and this is where I got the 350 equaled the Muncie built HD transmission.

Re: 3 on the tree question
 

Do you have pictures of your transmission? The two do look different. I am sure we could help you identify what you have with a picture. Or are you just trying to figure out what was stock?

This got me thinking so i looked on the gm heritage site and for a 68 like i have, the HD 3 speed is shown as an option. In 69 when the 350 became an option it is not listed. In 72 there were only two options, turbo hydromatic and 4 speed.

Re: 3 on the tree question
 

I'm trying to find what was stock. I bought the truck with no motor or transmission. I know the stock motor was a 350 but just trying to find the stock transmission to put back in it

Re: 3 on the tree question
 

Check this article out.

http://www.fourwheeler.com/features/...kward-glances/

I know it is more geared toward the K series, but it is the best one I have found regarding good info on RPO codes for 1972 trucks. Again I don’t know source of info so take it for what it is, but I am going with it being solid info.

According to the article, RPO code ZW4 is a Muncie SM330 3-speed. That info is about half way down the page.

Re: 3 on the tree question
 

Correct, but as you said this is for 4WD's. I have been looking into this because there is very little info on the 330's. That tranny came behind every engine 4x4 unless the SPID says otherwise. It also came behind BB cars.

With that being said, SPID is bare when it comes to tranny and its a 2WD. So it would have been the Saginaw.

Re: 3 on the tree question
 

Thank you I've been asking and doing some research. Everyone is saying its a saginaw

Re: 3 on the tree question
 

Travis my only question about is definitely being a Saginaw or not would go back to the RPO codes then. According to the pic I took of the GM Heritage truck spec page for 1972 said the 3-speed manual behind a 350 is RPO ZW4. The page from the article I linked said that RPO ZW4 was a Muncie 330. I think that regardless of what the SPID may show, the RPO for a trans in the truck line would be the same across all models. With that, he probably had a Muncie 330 as the standard 3-speed behind the 350.

Re: 3 on the tree question
 

I see what your saying but that article is wrong.

Just some observations:

IF the M330 was the "standard" issue transmission, why is there so little info on them/availability seems scarce
Saginaw-plenty of info, parts, forums. Not the case with the 330.

The 330 is fully synchronized (see page 5 and 6 below) the C series came with "3 speed steering column" while the K series had "fully synchronized 3 speed steering column"

https://www.gmheritagecenter.com/doc...olet-Truck.pdf

Multiple sites have RPO (ZW4) listed as "standard" transmission.

https://www.crankshaftcoalition.com/...PO_build_codes

Another website that has parts and part info.

http://www.drivetrain.com/parts_cata...peeds_v24.html

And this thread i came across about a month ago.

http://67-72chevytrucks.com/vboard/s...d.php?t=216510

I like looking this stuff up.

Re: 3 on the tree question
 

Great info Travis. Yeah I was digging through a couple of those too. I’ll tell you it has been a whole lot easier to find good solid info on the wife’s 71 F250 (yeah it’s a Ford). And damnit why didn’t Chevy foresee this craze taking off and document it better on the truck side?! That’s half the fun though. I tend to remember the stuff I dig up better anyhow. I unfortunately came to find out I was supposed to have the Muncie and it went the way of the original 4-bolt main 350 with a previous owner. It’s ok though as the wife said to just find another and replace it. Don’t have a line on one of those to go with the good info do ya Travis?

Re: 3 on the tree question
 

No sir, I believe that some of the square bodies came with the Muncie as well, unless your looking for correct casting dates. If I came across anything I'll shoot you the info.

Yeah it does seem Ford took better care of documenting, the fire that burned up all the GMC info didn't help any.