41 Cadillac Hydramatic flywheel cover cooling fins

[Ron Parker]

On page 18 of my 1941 Cadillac Hydramatic shop manual a photo shows cooling fins attached to the flywheel cover bolts.Both of my 41's do not have these.Any advice on weather I should find some to use? Thanks Ron Parker

[Chris Davis]

Great catch on the shop manual photo.  Like yours, my 41 hydramatic did not have anything like that when I removed the transmission. 

They aren't on the post war hydramatics nor do "fins" show up in any of my Master Chassis or hydramatic books.

Blue sky speculation is they were a hold over from the 1940 Oldsmobile configuration that was later discontinued and the fins then get lost or tossed when the transmission is removed or serviced.  An educated guess is they weren't that effective in rejecting heat - perhaps helping to push air around the enclosure had some benefit.

As others have noted, the WW II military hydramatics were water cooled - suggesting the engineers were concerned about heat rejection.

[savemy67]

Hello Ron,

If you plan to drive your car infrequently, and or short distances, I think you are probably OK doing without the cooling fins.  The Hydra-Matics for non-military use were produced for several years before cooling was introduced.

If you plan to drive your car in such a manner as to cause excessive heat in the transmission, you may want to consider finding or making the fins.  Although, as Chris mentioned, they can't be too effective.  I don't think there is a convenient way to connect an external cooler.

Respectfully submitted,

Christopher Winter

[Ron Parker]

Thanks, I live in Texas and it is too hot in the summer. I would run these if I can find some. I wondered why they had the louvers in the dust cover without some way to move air other than the round flywheel cover. They might make noise too.  Ron Parker