Trans Rebuild

The front main shaft has 10 teeth, the first gear on the shaft has 16 teeth, the number above the inspection plate is 18-4884434. If there is a certain picture you'd like to
See let me know .
 
The serial number is consistent with a V8 vehicle produced in 1939 so it should be a 78 case. The tooth count on the shaft you refer to as main shaft is not listed in any of my information. The main output shaft generally has helical and straight splines with exception to the early B-7061 which just has 6 straight splines but it was only used in the early ones from 32 through 35 or so. The main shaft has the syncho on the front followed by the 2nd gear then the 1st/reverse slider gear. The main input gear shaft is the first one at the front of the transmission. This one can be anything from 15 tooth to 19 tooth depending on the application. 10 tooth doesn't fit into this scenario. My guess is that you are referring to the splines at the front. All the light duty 3-speeds up through 1948 for cars and up thru 1952 for pickups have 1 3/8 inch 10-spline shaft to fit the clutch disk in front.

Here is a good breakdown from Mac VanPelt's site. http://www.vanpeltsales.com/FH_web/FH_images/FH_trans-pics/Flathead_Trans_1936-52-LD3spd.jpg
 
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Rear to trans is 6 spline, front to engine is 10spline This is all new to me so please be patient
 
No problem, we all learned this stuff somewhere.

All of those parts numbers on the illustration from VanPelt's are the basic number for all of those early Ford transmissions. The prefix is where a person can tell what year grouping it was made to fit. You might have a look at the four different synchronizers in the lower illustration block. Yours would have had either the top left one or the top right one. The top left one is the early style and has the beveled edges. The top right one is the 1939 type that looks more like two hat bushings back to back. Can you tell which one you have? It makes some difference about how things come apart and go together is the reason I ask.
 
IMG_3208.jpg
A picture of the gears, looks like a early syncro to me
 
Yah, it looks like the corrosion is a lot of your problem there. The early type synchro was likely used up in the commercial pickup line in 1939. There are a few parts that interchange with the later gear sets but you may be better off looking for another set of gears. You can scavenge them out of any of the 1939 through 1950 top loaders or 1940 through 1948 side loaders. Folks that are updating the old cars to later drive line will sell this stuff pretty cheap sometimes. Mac VanPelt's book will let you know what you can use out of that one for an update as long as the parts aren't too badly eaten up. The cluster might be OK but it looks pretty ate up in there.
 
I've not read the whole thread, but to be honest . . . to replace all of those components will cost a huge amount (if bought one by one). I would seriously look for another transmission as you'll have very few components that you'll be able to reuse in this one. This is about the most rusted/corroded transmission that I've seen . . . I would definitely not be planning on using almost anything that is inside of it.

Just trying to save you some costs and efforts -- start with a better donor and your life will be a LOT better.

Best of luck,
D
 
Was already looking for one. Saw one for $1200 and one for $800 both not including shipping. What would be a reasonable pice???
 
KarlJS said:
Was already looking for one. Saw one for $1200 and one for $800 both not including shipping. What would be a reasonable pice???
Click to expand...

Couple things to think about . . . I would not buy a used 39 transmission for those kind of prices - unless they are from a reputable builder who guarantees their work. With that said, it is surely possible to pay $1200+ for a quality rebuilt one - without you supplying a core for them to rebuild. I know that I'd have to get at least $1200 for a good 39 trans . . . probably closer to $1500 if it has all the right parts, has some modifications for oil-leakage control, special bushing for 2nd gear, etc.. In the end, get the best you can afford from somebody with a great reputation and who will support their work.

Also, the transmission that came out of your truck was not a 39 . . . so you'll be much better off with a real 39 trans once you find a great one.

I would talk to Mac VanPelt, Charlie, Mike from ThirdGen and the original link I posted for the Early V8 garage. See if any of them have a 39 trans that they have rebuilt - with all the right stuff . . . so you can hopefully purchase a good quality rebuilt from somebody you can trust.

Good luck!
D
 
If it means anything Karl. I had a nice clean 37 top loader case and a nice 46 side shift trans. I installed the gears from the 46 in to the 37 case. And found a 3 speed top with the double detents and it worked out perfect in my roadster. Just a thought for you and you can usually find side shift Trans's fairly reasonable. Mac Van Pelts book is a savor. Good luck with yours.
 
When I bought my '39 p/u the trans popped out of 2nd going up or down. I found a '39 trans with the later syncos locally from an old hot rodder who replaced it with a C4 since shifting was getting to be an issue for him. Paid $500.00 for it, filled it with ****** fluid after installing and haven't had a bit of trouble with it. Keep looking, I'm sure you'll find a trans in SoCal so you won't have to have it shipped. There is a swap meet Saturday June 10th at the Little League Headquarters in Devore that might be worth checking out. It's put on by a Model T club but I always see later flathead stuff there as well, plus its free admission and free parking.
 
IMG_3210.jpg. Being new at this. Is this something that would fit? I actually have a 8BA 24 bolt engine in the truck. I'd really like to keep the stock drive train. Thanks
 
One of the guys mentioned that this wasn't a 39 transmission but it is likely the original transmission that came with that truck if the number on top matches the frame number. Commercial pickups didn't have the late type synchro until the old style ones were used up in 1939. If I were you, I clean and inspect that old case to see if it is useable. If it has the original VIN on it that matches frame number and title, I'd want to keep it and just update it with later gear parts. As nasty as things look in there, there still may be salvageable parts. I wouldn't use anything that is rust pitted up but wouldn't hesitate to use stuff that is still otherwise in serviceable condition. If the case is bad the one pictured above would work as a replacement. Be wary of rust bucket replacement units. Ask a lot of questions before purchasing sight unseen. You don't need a cleaned up version of what you already have

The trans you have in the posted photo above is for the 1942 through 1950 Ford pickups with open drive unless it is the rare 51/52 top loader with the 1C gears in it. It can easily be converted back to closed drive but you will need the closed drive main output shaft to go along with it. Side loader transmissions from 1940 to 1948 have all the parts a person needs to build up a top loader since the case & shift mechanism are the only parts that are different. These are generally valued in the 400 to 500 dollar range if they need overhaul since most folks are looking for the top shift case.

You can change the pickup to open drive but that's a lot of work since it would either need to be converted to dual rear springs like the 1942 & later pickups or a torque arm would have to be installed along with radius rod mods to use an open drive shaft with the old type transverse buggy spring rear.
 
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Karl, I strongly suggest you get in touch with the Early Ford V8 Club, Group 11, with members all around you in SoCal ... via Google.

Your need for first hand guidance is obvious. Plus, at least one guy may have a transmission for you.

Ford Barn is a wonderful source for help, but sometimes the advice is overwhelming.
 
Karl, another good swap meet is the Fathers Day Roadster Show at Pomona. June 17th. A lot of early ford parts and other stuff. I usually do just for the swap meet and not the roadster show. To many to look at. And as rotorwrench stated, if you can salvage you trans case you can probably pick up a side shift trans very reasonable. Carry a 1/2" box wrench with you so you can pop off the side cover to inspect, that is if you find one. Just my 2 cents.
 
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