Dynaflow

[West Peterson]

Based on research that a friend and I have been conducting, the Dynaflow transmission for 1949 should mostly be painted black, with the exception of a spacer and possibly the oil pan. In some illustrations that we see, it appears the oil pan may be painted engine color, or silver. Something lighter than black. Is there any solid information that would prove this correct or not?

[1953mack]

Are you calling the torque converter's reaction flange a spacer?

There's a lot of noise on this Forum that talks about a painted-black Dynaflow transmission as being a Buick factory replacement unit or one from an independent rebuilder only --- opposed to what the OE units were when they rolled off the assembly line ---  unpainted aluminum reaction flange, bell housing, cast iron case, and stamped breather cover. 

 

Al Malachowski

BCA #8965

"500 Miles West of Flint"

[West Peterson]

Thanks, Al. Here are two of the Buick manual illustrations for which we are basing our question.

[West Peterson]

While it looks obvious that the above illustrations show a bell housing that is quite dark, this photo from Bob Engle also leads one to believe that all the "raw" metals seem to take on different colors.

[1953mack]

The bell housing in your Shop Manual picture, Post #3, looks more like cast iron, whereas the one shown in your colored picture immediately above looks more like a cast aluminum bell housing to me. Correct assumption on the latter?

 

Al Malachowski

BCA #8965

"500 Miles West of Flint" 

[buick man]

… our opinion from what we have seen over many years is that since the bell housing were aluminum it was left cast and unpainted from the factory.  The main central valve body area sections were painted a dark gray or black and the rear sections were left cast surface as well. We have always seen original trans pans factory painted as the same color as the engine.  The differing color combos and natural or not components are do doubt due to the fact that these sections were manufactured at different area/sites and then shipped or brought together into or at the factory and assembly on site at the transmission assembly/test section department  then transported to the assembly line by the factory parts gophers when and where needed.

 

The photo posted above appears to have a spray painted bell housing and what appears to be an overspray onto the rear section tube assembly.  We would venture to state in our opinion the bell housing shown was bench painted separately during overhaul as can be evidenced by the indicated resulting smooth finish on the bell housing as these cast bell housing were not as smooth as when paint has been applied.  If not painted silver, this same effect can be achieved by glass bead blasting the aluminum bell housings down to # 7 or # 3 bead and to a point of rendering a smooth consistent surface that mimics a faux silver cad or alumi-blast spray can paint job.

[West Peterson]

Interesting, and thanks for the added information.

I'm almost certain my friend has informed me the bell housing on his 1949 is iron. I'll double check. If it is iron, that would probably explain why it looks painted in the above illustrations.

[Leif Holmberg]

1956 was the first year with aluminum bell housing.Even the first year the Dynaflow fit on all models.Earlier there was at least 2 different length on Dynaflow each year.Even as late as 1956 they where unpainted.

Leif in Sweden