What application year for this Dynaflow Transmission ?

[buick man]

First off I am getting into the mindset of dropping my Dynaflow and resealing it but have not as of yet. Recently I came across this guy who reports to have a 1957 Dynaflow for sale that he rebuilt. It would be nice to have a collection of photos from 48-65 with all the different dynaflows side by side so one could see how they evolved.

O.K. I have posted a few photos of this transmission. He claims to have then bolted it onto a rebuilt 401 nailhead motor he was intending for his Hot Rod build-up that never materialized. However with this said upon examination - The case number on this case housing top does not correspond to the case housing number from my Motor's Flat Rate & Parts Manual ( 1962 ) which reports the following numbers: Transmission Case Numbers 1955/ 1166589, 1956-60 / 1389282, 1961-1962 1196119 respectively. The case number on the one I refer to here is 1342992-4 and the long aft housing.

I did some research here and it appears Shadetree has posted a 1952 Dynaflow (as pictured below with the red arrow) with the same case number but upon closer examination it appears to have a somewhat different topography and shape design to it around the stamped numbers.

Now in the past I have read it is hard to go by these case number codes as gospel. Don't know if that concept is true or not. So upon examination just what exactly does one look for to determine if this is indeed for a 1957/58 Buick application as the seller has implied?

So is this guys Dynaflow for and from a 1957 Buick?

Edited April 8, 2013 by buick man (see edit history)

[Guest kaycee]

I'll check my Buick parts manual tomorrow, but first of all the last Dynaflow used was 1963.

What year are you working on? In '55 they came out with the twin turbine variable pitch unit. The case numbers won't help me in my parts manual other than I can look up the different parts used in various years.

kaycee

[Guest kaycee]

I'll know when you give me the year and model that you're working on, but is the car you need one for have a torque tube or open driveshaft rear axle? They went to an open driveshaft in 1961, and one other thing, the 1952 would have a straight eight not a nailhead.

kaycee

[buick man]

Thanks kaycee for the input but I too am aware of all of these factors you speak of.

Yes 1963 of course. That was a typo. The 64 & 65 used the then new turbo hydramatic or super turbine 300 2-speed & 400 3-speed respectively. The only real changes 53 on to 57/58 was in the stators assemblies, pump and torque converters with the main planetary gears in the center section little unchanged so perhaps this center housing changed little as well. Or with these thoughts, perhaps he the seller or someone else pieced together this transmission from an earlier pre 57 Buick housing coupled to a 57/58 bell housing and torque tube assembly? I am working on my 1957 Buick and want to use this as a secondary backup or as a parts provider.

Edited April 8, 2013 by buick man (see edit history)

[Leif Holmberg]

You can do a search for "dynaflow identification" on AACA and you will get a lot of threads about it.Here are the one that we have tryed fix to make it easier for people to find the right year of Dynaflow.

Leif in Sweden.There are a different bolt patten on 1956 and earlier dynaflow than on 1957 and later. I think a lot of the cast numbers are the same on those 1950s Dynaflow: s.

http://forums.aaca.org/f162/dynaflow-code-letters-1953-59-a-328330.html

[Bhigdog]

Boy that guy is GOOD. It looks like he rebuilt it without taking it apart. Neat trick not getting any oil along casting part lines. Maybe he did it orthoscopicly.................Bob

[buick man]

No he rebuilds dynaflows and has for years as a part-time gig. He is in his late 60's now. This was sitting in his garage for about 5 years after the rebuild. So I am told. It would make a good parts donor and that is why I am interested in it.

Does anyone have a Motors Flat Rate and Parts Manual from 1956 and back to say 1950 or so. It would tell us the case number for these years too. I only go to 56 and forward.

Edit: Oh and thank you Leif for that link. I was following it last year as well. I forgot all about the stamped number emboss under near the accumulator. I will look and report back as well as on my 57 too. I was interested however, in the number stamped on the casing at the top of the transmission. As per my books these case numbers were suppose to change. I still want to get someone in the know regarding to explain if these case numbers were as diligent a reference as the I.D. number is that lamar has gathered together on this link.

Edited April 9, 2013 by buick man (see edit history)

[buick man]

Update: This transmission has the I.D. stamp R005 and 28 embossed within a square which is located on the upper band next to the bell housing. This makes it a 1957 unit even though the case number says otherwise according to my Motors Parts Manual. The case area is also where the I.D. stamp is located on. The I.D. stamped on my 57 that is still in the car is RO27. Apparently the case numbers molded into the upper top center area of the central case does not necessarily indicate the year. It will be interesting to see what the number is on my 57 that is still installed once I remove it. I will report back at that time. This survivor car has the transmission painted the same blue emerald color as the engine. There was a question in I believe one of Shadetree's posts inquiring about if Buick painted the Dynaflow or left it bare. This should confirm that Buick indeed painted the dynaflows and the color from the factory was the same as the engine. Blue Emerald .

[TexasJohn55]

buick man, I have 2 GM part # references on Dynaflows. What we really need is documentation of casting # relationship to published pn's, as well as the relevence of casting # revisions or suffix #s. My 55 Special has center case casting # 1342992-5 but pn is supposed to be 1389450. My bell housing has casting # 1163913-3 and pn is published as 1163913. We need more reference data to unravel this mystery. TexasJohn55

Edited April 17, 2013 by TexasJohn55 (see edit history)

[Leif Holmberg]

Sameone that have been working with those Dynaflow in early days or even later must have som identification number (other than the letters) or casting number to referer to.It seems that the Dynaflow ident. is hard to to find on internet as well.

Leif in Sweden.