# 65 GTO with Saginaw Corvette transmission?



## Glasgow65GTO (Jun 14, 2020)

So I was looking for the identification numbers on my transmission in my 1965 GTO and couldn’t locate them so I looked up the housing numbers and they all match up with the Saginaw Corvette transmission. Is my transmission not original like I thought? This is an early production 65 goat.


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## BLK69JUDGE (Jun 10, 2010)

its cast iron ??? not many vettes or gtos that I can think of came with cast iron saginaws .......

hmmmmmmmmmm

in 65 case number above the fill plug should end in a 325 and case is aluminum


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## GTOJUNIOR (Aug 7, 2011)

There were 2 Cast Iron 3 speed offerings and 2 Aluminum 4 speeds for '65


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## Glasgow65GTO (Jun 14, 2020)

It’s a 3 speed.


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## GTOJUNIOR (Aug 7, 2011)

Looks like the Stanard Duty M12 
This was a GM/Muncie Cast Iron case. 
Book says used until 3/65


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## Glasgow65GTO (Jun 14, 2020)

See #341 looks exactly like it.


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## GTOJUNIOR (Aug 7, 2011)

Exactly, GM used them across the board including Pontiacs.
The Pontiac books don't go into great detail but list as an X and/or FD coded trans


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## Glasgow65GTO (Jun 14, 2020)

Yeah I freaked out when I couldn’t find the “X” on the transmission. So you are saying this is original to my car? Sorry but I’m pretty new to this game of identifying things.


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## PontiacJim (Dec 29, 2012)

Glasgow65GTO said:


> Yeah I freaked out when I couldn’t find the “X” on the transmission. So you are saying this is original to my car? Sorry but I’m pretty new to this game of identifying things.


Yes, original to your car. The "standard" transmission on the GTO was the manual 3-speed. Optional trans were the ST-300 auto & 4-speed. If I am correct, I think the later '65 GTO began to use the HD Ford 3-speed manual transmission which was carried over for several years on Pontiacs.

Get the PHS documents for your car and it will verify what your car originally had in it for driveline and options.


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## Glasgow65GTO (Jun 14, 2020)

Yes I know that it came with the standard 3 speed, but I was trying to determine if it was the original one that was installed at the factory. I really appreciate all this info. I read somewhere that the last few digits of the vin number would be stamped somewhere on the tranny behind the number 2, but could not find it. I guess it doesn’t really matter that much.


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## Glasgow65GTO (Jun 14, 2020)




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## GTOJUNIOR (Aug 7, 2011)




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## Glasgow65GTO (Jun 14, 2020)

Wow! That’s a cool guide!














This is what I have right now.


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## BLK69JUDGE (Jun 10, 2010)

K 64 dates on the case and tailshaft so it may be the original

I was thinkin 4 speed sorry


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## GTOJUNIOR (Aug 7, 2011)

The Resto Guide is a good book,
but as the title implies, it's a "GUIDE" and there are known holes in some of the information that was never filled in.


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## O52 (Jan 27, 2019)

In my opinion it was primarily written for the 64-67 cars. The first edition didn't include the 71 or 72 models and the 2nd edition treats them as an afterthought. Since it was written more information has become available making it more of a guide as JR mentioned, then as an authoritative source.


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## Glasgow65GTO (Jun 14, 2020)

The tag on tail shaft says K 24 and the housing says K 204


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## gtomike455 (May 24, 2020)

Glasgow65GTO said:


> So I was looking for the identification numbers on my transmission in my 1965 GTO and couldn’t locate them so I looked up the housing numbers and they all match up with the Saginaw Corvette transmission. Is my transmission not original like I thought? This is an early production 65 goat.
> [/QUOTE
> 65 gto came with muncies, m20 or m21.


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