adding 39 syncro cluster in 37 trans box posible?

im looking at geting a 37 ford T3 trans so i can start mocking up my flathead, trans and banjo in my model A frame for welding but i must know if the 39 syncro cluster will fit in the 37 trans box? do i need to do some mad doctoring? or just keep looking?

thank you for your time
Telecustom

 

I believe so. What is the number on your case? Im pretty sure the "78" ones fit.

 

so yesterday i picked up two 1937 t3 trans, one open drive and the other closed, the open is in great shape and still full of clean fluid, the closed is empty missing the shifter shaft and the cluster is some what rusty and wont move. but both the casings are 78's

 

Further, the cluster is the same part, introduced in 1936. The '36-8 gears have the same teeth as the '39's...different synchro theeth are the change, and that has no impact on the cluster. If you can find a '39--51 type fork, that can be transplanted into the '36-8 top, but usually you have to buy a top to get the fork anyhow.

This old post contains enough info to ID all your cases and what is inside them...remember that innards may differ in vintage from case!

http://www.jalopyjournal.com/forum/showthread.php?t=91515&highlight=1939+trans+prices&showall=1

 

Thank you Bruce for directing me to that old post i now know that my open drive trans is a 78 casing with the later 1939 29 tooth syncro, now my other trans is the early 1936 syncro with 48 casing. but i now need to change my main shaft on the 78 to shorter 9.90'' closed drive later main shaft, and still use the mounting bracket off the earlyer '48'? because im running a model a banjo. enyone want to trade a closed drive main shaft for open drive?

 

As you say the open drive is the later gears, just because its open drive. The open drive came in '42 with the 1/2 ton pickups. I have the shorter output shaft in some of my stuff that I got that I can give up (I am collecting parts for the open drive) I don't have the torque tube rear mount to go with it though. I don't really need the open drive output -- I have 2 of those right now as well. What I could use is a 28 tooth input shaft that will work with the newer ('39) style syncros

 

nice but i dont have a spare 28 tooth input shaft... i do have some pics of what im dealing with, the late trans, early trans, banjo mount, and im selling a 1946 t4 truck trans

 

Don't worry -- I will send you a PM to keep any possible transaction off the board.

I don't know enough about all of the torque tube stuff. Not sure what all changed over the years. I know that they used several different rear bearing retainers. I do believe that you are correct that since you are planning on running the newer gear set, you need to get a newer output shaft as well. But I can't be certain that all of this will work with your Model A torque tube?

 

You need to change 2nd and input and the fork, probably a cup or two of miscellaeous washers. For an easy list...HRM and CC posted basic speedshop info on converting to LZ gears in the various generations of flathead transmissions; if someone can scan one of those, it covers all issues...same process as changeover from '36-9 Ford stuff to '39-48 Ford stuff.

 

Bruce, correct me if I am wrong, but in one of the posts telecustom said that the transmission that he is going to work with is an open drive transmission with the '39 + gears (by default it has to have the '39 + gears since it is open drive). Its kindof a long story, but I bought a trans from a guy that had been a conversion, so it has what I would assume are '40 + car gears in a "48" series case. When I bought it I thought I had a true '39 until I got the rear of the case cleaned up and saw the "48"

Assuming we both have '39 + gear sets, if I give telecustom just my output shaft, shouldn't it just swap into his gear set?

 

There are a couple of different splines possible, including a 1951-2 open one that won't fit any other gearset. I know very little about the open drive stuff...probably well covered in Van Pelt's book?
All the V8 bearing retainers interchange, all the TT ones can fit Model A...that end is not a problem. I'd start taking stuff apart and see if available bits fit one another. There is no disadvantage to the 48 case. Easiest and usually cheapest way is usually to buy a whole '40-48 trans as the donor!