Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => General Discussion => Topic started by: bill_boos on January 25, 2020, 04:40:23 PM

Title: 1947 Cadillac Hydra-matic MYSTERY
Post by: bill_boos on January 25, 2020, 04:40:23 PM
MY '47 Series 62 Cadillac Sedanette Hydra-matic has DR and LO indicators on the shift lever but THREE detent positions to the right of Neutral. The first is four speed, the second is three speed and the third is two speed. I thought the car had only a four speed and single speed low.

Might I have a later year Hydra-matic installed. Were there Hydra-matics with a DR, 3, 2  system that would work with the original engine and shift lever? The engine is a flathead so it is likely original.

Any thoughts or knowledge?

Bill

Title: Re: 1947 Cadillac Hydra-matic MYSTERY
Post by: k8096 on January 25, 2020, 06:40:20 PM
Yes, it appears your car has a later dual range Hyrdamatic installed.   That's OK, it's an improvement as you can hold it in 3rd gear if you want to.   It's probably from a 1953-55 car.   I wouldn't worry about finding a 1947 Hydramatic, just enjoy the car as is.   On the 1947 Hyrdamatic, "Lo" actually holds it in 2nd gear, not 1st.       
Title: Re: 1947 Cadillac Hydra-matic MYSTERY
Post by: bill_boos on January 25, 2020, 10:58:37 PM
J, thanks for verifying what I suspected but had no idea if that was the case or what years it might be from. It shifts smoothly and with good power and am glad to hear it is an improvement not only holding third gear but perhaps better engineered and built since it was later in the development of fairly new technology.

I wouldn't swap it out for authenticity -  I am more interested in drivability although the car is quite authentic  except for dual Optima batteries and an electric fuel pump that I never use.  I'm sorting out a couple of issues that I will post to ask for help. I've gotten so much help already that I just now joined the CLC so I can support the club.
Title: Re: 1947 Cadillac Hydra-matic MYSTERY
Post by: Bob Schuman on January 26, 2020, 10:04:21 AM
Bill,
If you want to know what year your transmission is, look at the data plate attached to the passenger side of the transmission case. It should start with C-52-, indicating a Cadillac 1952 transmission, C-53 for 1953 and so on. If it should start with O instead of C, that's an Olds transmission, just as good as one with a C, no cause for concern.
Title: Re: 1947 Cadillac Hydra-matic MYSTERY
Post by: fishnjim on January 26, 2020, 10:06:49 AM
check the tag for the trans number.   Then cross reference to year to B sure.   

There's a lot of hoopla.   Even though the shift lever only has two positions, my '58 "C" is actually a 4 speed.   Two in each position.   Read up on hydromatics evolution.
https://en.wikipedia.org/wiki/Hydramatic

"mystery" = lack of info indicated.