1951 Plymouth overdrive?

I recently bought a 1951 Cranbrook convertible. The car has overdrive, but in doing research I keep reading that overdrive was first offered in 1952.If it matters, the car may have been made for Canada. Was it possible to get overdrive in '51?

I've owned several '51-'52 Plymouths and done a lot of research on them. Overdrive came out as a mid-year option in 1952. Overdrive-equipped cars got a chrome 'Overdrive' nameplate on the lower right side of the trunk lid. There was even a revised edition of the owner's manual printed to coincide with its introduction.

Canadian-built cars had a 'long-block' flathead six; U.S. had the shorter 23" version. They also had a body trim plate on the firewall giving the paint color that was not used on U.S.A. cars.

Are you sure your car is a 1951 model? I've seen many Plymouths listed with the wrong model year because the cars were very similar to the '52's. There really are many subtle differences between both years beyond the variations in trim and nameplates. Have you tried decoding your VIN?

Many earlier cars have been retrofitted with overdrive through the years and yours may be one of them.

If you have any more questions let me know. I'd be happy to help.

Harold

Hi Harold. I also wondered if the car might be a '52, but the VIN fits within the range of id. numbers from the 51's built in L.A. Also, I read an article which listed some differences between the '51 and '52, such as for the '51 the name Plymouth on the glove box door vs. no name for the '52, and the hand brake handle in chrome for the '51 vs. plastic for the '52. All these things indicate that my car is in fact a '51. Perhaps, as you say, over the years someone retrofitted the car with the overdrive. Right now the car is at my mechanic's, but when I get it back I'll do some more checking. Thanks for offering to be a resource. No doubt I'll take you up on it. Feel free to contact me directly at jim108@comcast.net.

It is my understanding from all I have read that when the Plymouth got the overdrive (R10 unit ) in June of 1952 the dealerships were afforded OD retrofit kits to install on customer cars. It could very well be a dealer installed unit and considered correct.

As for identifying 51/52 years..there are a number of markers defining the two but it has been my experience on a car that is not extremely well documented that parts replacement due to minor body damage and normal wear and tear could very well have been replaced from whatever was at hand as normal upkeep over the years. Some items could have carried over as this has been argued back and forth for a long time..One of the best methods to determine the actual year would be the wiring loom to the engine..51 throughthe firewall and 52 through be cowl.