1950 plymouth rearend gears

what size gears are in the 1950 plymouth sd coupe, and are they good gears for long distance cruising. also could you change the yoke to accepi a different driveshaft (GM) The old one has a four bolt type thing on there. Any help is appreciated, Stan in Pa.

 

Change the entire rearend out. They have tapered axles which require a heavy duty puller to remove and I'm sure it has like a 4.11:1 gear with that little six.

For what a rearend costs in a you-pick junkyard you're going to be miles ahead to get something the right width and put perches on it to fit. Speedway sells Mopar branded perches for under $20.

 

I believe standard Plymouth gear ratio for most of the US was 3.90, with 4.11 for mountainous areas. Plymouth didn't get OD transmissions as an option 'til '52 and they too, were 4.11.

Rustynewyorker 's advice is correct. Change out the rear end for later Mopar, Jeep Cherokee or 8" Ford or ??????? The benefits are better choice of gear ratios AND a parking brake assembly in the rear brakes.

Ray

 

My book says 1949/1950 "Available rear axle gear ratios (Various). For 1951 P-22 3.73:1 or 3.90:1 ,P-23 3.90:1 or 4.11:1. So looks like it would be rather low ratio. Thats why Plymouth sold ODs later on. Ter409

 

Thanks guys for getting back to my post. This is my first Frame Off restore, at 63 years old. Took the project on by feeling i need to do something positive instead of just sitting around. I used to do quarter miles back in 69, when i got back from Vietnam. So, i'm still pretty handy with the Garage and have all the tools needed, save for a metal brake. All your inputs will allow me to continue on a straight path to complete this task. So Ter409, HNStray,NewYorker and Missori Marv,Your all music to my ears, Stan in Pa.

 

SWALUDA my dad bought a brand new 1954 Plymouth Belvedere and I remember it well. It was our main travel car until 1964. With the overdrive it traveled along in the 60 to 65 mph range all the time. In 1963 Mom and all us kids took a 2000 mile trip and I was incharge of checking the water and oil as dad was working and could not go with us. The Plymouths of that era drove very well. Good Luck with your project. Ter409

 

As been said, your likely gearings are either 3:90 or 4:11 on that tapered rear axle. I got a 67 newport C body axle for my 40 plymouth- fits the spring perches fine and is just a tad wider at the flanges but I now have bendix self adusting brakes rather than the lockheed non adjusters...disc brakes are an aftermarket offering for the 8 3/4 rear. I've heard guys running explorer axles with discs too.
The optimum ratio is around 3:55 with or even without an OD trans..3:23ish is a little too tight and 3:70ish and higher is too loose but workable if your running a V8 that can swing higher rpms easily but I've heard flatheads that can only hit 3600rpms using an OD trans and 3:90-4:10 gears and running 65mph just fine- but there's not much left for passing with that set up.

 

BTW- just curious, what motor/trans do you plan on using for you 50?
I don't judge, if you want a sbc that's fine...if you want to keep a flathead 6 that's cool too.

 

I've got a '50 Special Deluxe sedan that I'm currently working on so I'll be interested to see what rear end you finally end up choosing.

Dave

 

Undecided which combo engine , trans , rear. Im trying to get all my research in to be able to come up with, the most reliable, easiest, cost efficient, Highway cruiser pushing up to 400 horse. Kinda like a new old Moonshiner. Any ideas or tips will be seriously evaluated. I am currently outside the U.S. and expect to return in April. I bought this unit in July of 2012. 6 was frozen and yanked along with tranny and driveshaft. Interior gutted, dash removed, front clip removed, back fenders removed, glass out. Sandblasted about 70%. Started cutting floors for pan and brace replacements, Not much Rust outside, More inside. I need a V8 because i want to do a lot of Highway. I have a long way to go but accomplished what i did , alone and in a months time wit a broken shoulder. soo. the drive has no end and i dont want to get disqusted or bogged down with no direction to go. Thanks Stan

 

Cheap and easy, go a sbc with a GM OD trans..auto or manual...your call.
If you want to be a semi purist, go sbm and an A500 or 518 mopar trans.
Go ford if ya like...maybe a GNX V6...depends on what you like or what you can find. Anything to get another mopar out on the road!
There's alot of engine mounting options out there including the easy biscuit mounts over the frame rails or weld ins.
There's front disc set ups for your oem front end and dual brake MCs that can be swapped in or mounted elsewhere for better braking..if ya go faster you'll need to stop better! Use a front half with a mustang II suspension for nicer ride.
You've got alot of options here and options are a wonderful thing!

 

My 1950 Plymouth Deluxe 3-Window Coupe has stock 3:73 gearing and is not worth a damn to go over 60 for any length of time at all. It's simply revving too high at that point. I need to come up with a rear end that is the right width to go under it with about a 3:00 set of gears. If anyone knows of a Dodge, Plymouth or Ford rear with the correct with and ratio, PLEASE drop me a note here.
Thanks!!!
J. R.

 

This is the ride that it needs to go under!

 

Ford Explorer 8.8, 6-cylinder, 3.27:1 gears, drums early, discs late.

Jeep Cherokee XJ (not Grand Cherokee) Dana/Spicer 35c, or Chrysler 8.25, after 1996, manual transmission, 3.08:1 gears, drums.

Both have the same wheel bolt pattern as original The Explorer is 59-1/2" wide. The Cherokee is 58-1/2" to 60" wide.

Put a T5 in it, and a fresh rear with 3.73:1 gears. You will keep the low end, and get more on top.

 

It sounds as if the Explorer or Cherokee is likely the route to go.
I'll have to lock in on the best dimensions to use after taking some measurements once again to be certain as to what works best.

 

Plymouths that age were made for a straight six engine, period. This makes it difficult to squeeze in a V8 because of the steering box. Easiest fit I have seen, is a Chev small block V8.

An alternative is the bigger flathead six out of a Chrysler Windsor or DeSoto. Up to 265 cu in and will make your light weight Plymouth run down the hiway just fine. Practically a bolt in except you need to move the motor mounts forward 2" and set the rad ahead of the rad support.

For your project the Chev is probably best. Although, I have not checked a Ford 302 which is a pretty narrow motor.