Overdrive For 1937-48 Cadillac-LaSalle Transmission?

[carlhungness]

Has anyone ever seen an overdrive adapted to a 1937-48 Cad-LaSalle transmission. If so which overdrive  was used?

[jackworstell]

I haven't seen an overdrive on these cars.....but on our 1937 series 60 we switched out the "pig"
for one from an early 1950s Cadillac with Hydramatic...these are   3.07 ratio.

We had to grind the housing just a little and had to change the driveshaft
( for a somewhat shorter one as I recall ).
We also had to use 1941 Cadillac axles....which we had to shorten by about 1" each as I recall....we
had to do this to get axle splines which would match the splines in the early 1950s "pig"

Of course overdrive would be better....but a lot more work and expense.

We are happy with the results using the 3.07 pig

Jack Worstell     jlwmaster@aol.com

[Steve Passmore]

Yes, I have an overdrive conversion on my 37 Convertible. It took years to perfect and a lot of machining. Most work was done by a company in your country in the 80s who are now defunct.  It uses the rear of an early 60s Chev manual box with overdrive.
Problem with just raising the rear ratio is the clutch will suffer in the long run on lots of hill starts.  I ran mine  many years ago without controls (fixed in high)and the clutch went out in a year. I also got stuck on a few hills where she just couldn't pull away, OK now though.

[35-709]

These folks might provide an (expensive) option ---

https://www.gearvendors.com/index.html 

[carlhungness]

I have heard of gear vendors, so thanks for the suggestion. I have enough machining skills and friends who have a lot more to get the job done so I'm looking for the easy way out, finding someone who has already done it.

[carlhungness]

For Steve Passmore: I am assuming the machine shop removed the tail section of your transmission and adapted an overdrive, am I correct? Any more details you can share to help me along would be appreciated. If they did it, I can do it so I'm trying to figure out what they did. After all, it's just shafts and gears that go in a straight line and I'm wondering what they adapted to what to make it all work.

[savemy67]

Hello Carl,

If I recall correctly, Borg Warner made about 2 million overdrives for GM between WWII (possibly before) through about 1970 - the later years mostly for trucks.  The unit was usually mated to a Saginaw 3-speed manual transmission.  The overdrive was a planetary gear unit with a one-way roller clutch.  The controls included a manual cable, a solenoid, a governor, and a wiring harness that included connections at the carburetor and ignition coil.

The big challenges in adapting a unit to a Cadillac manual transmission would be altering the output shaft and splines of the Cadillac transmission to fit the splines of the overdrive planet carrier, and machining a plate to adapt the overdrive to the rear of the Cadillac transmission case.  This plate would also have to be machined to accommodate some of the overdrive components like the solenoid.

If you love working with metal and cars, this is a worthy project.  The difficulty is acquiring one of the Borg Warner units.  Less difficult is acquiring a late '50s Chevrolet shop manual which will have the description of how the overdrive operates, is controlled, and rebuilt.  The manual will probably not have dimensional specs for the parts.

Years ago, I watched a video on the Internet of a fellow who adapted a Borg Warner unit to a Muncie 4-speed.  Obviously, this was easier than adapting to a Cadillac 3-speed.  I recall that Ford also had overdrives in the late '50s, but I don't know if Borg Warner made them for Ford.

Christopher Winter

[carlhungness]

I agree, and I like worthwhile projects. Most of my sculptures take at least 2,000 hours and I put in more than double that on my latest book, a biography of Carl Fisher, inventor of the Indianapolis Motor Speedway, Miami Beach, Florida and father of the Lincoln Highway. It took 17 years worth of part time research and $55,000.
I do want an overdrive.

[Steve Passmore]

Then Gear Venders is the way to go Carl.  I had never heard of them when I started my project early 80s.

[The Tassie Devil(le)]

I would be going the Gear Vendors route.

There should be sufficient room between the end of the transmission and the third member to install a unit, without compromising driveability.

Bruce.

[carlhungness]

   Gear Vendors will charge at least $2,500 for their basic unit and I feel confident I can adapt something for half that.

[Steve Passmore]

Beilieve me, after making mine 'Gear Venders' would have been a cheap route.

[jmscan06]

A company called Overdrive Spares sells a Laycock conversion unit that costs a little less than the Gear venders.    Go to http://www.odspares.com/.   Look under conversion units.


John Scanlan
CLC # 28099
1940 Lasalle 5227c

[carlhungness]

Thanks for the info John, I'll compare pricing, machining, total work, etc. so the site you provided will help.

[jmscan06]

This is another company that sells Laycock remote overdrive units.  OverDrive Repair Services. 

www.overdrive-repairs.co.uk/products.php?cat=Overdrive


John Scanlan
CLC 28099

[Steve Passmore]

This is another company that sells Laycock remote overdrive units.  OverDrive Repair Services. 

www.overdrive-repairs.co.uk/products.php?cat=Overdrive


John Scanlan
CLC 28099

Bare in mind this company is in the UK.