Trans Rebuild

[KarlJS]

I live in Riverside California and am wondering if there are any recommendations for someone to rebuild a3 speed top loader out of my 39' 1/2 ton truck. Thanks

[flatford39]

They are really easy to work on. Pick up Tardell's and Van Pelts transmission books and do it your self. Van Pelts will have all the parts you need.

I never worked on a trans in my life and about a month ago I replaced all the gears and guts in my 39 top loader with gears and guts from a 46 48 side shift trans. Took about an hour and I had no parts left over on the bench. That in itself is a success sometimes.

[Talkwrench]

I think if you can get it out yourself then you must be fairly mechanically minded... From there take a look yourself. As said get the book.

[KarlJS]

Giving it some serious thought on doing it myself. Thanks guys!

[39wagon]

X3 on doing it yourself. Hardest part is getting it out of the frame and onto the workbench. I too had never tackled a transmission but did it in a day (39 toploader) after I got Van Pelt's book and parts. His products are great as is his information. He also answer's his phone and is quite helpful.

[Bored&Stroked]

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Hey Karl: They are pretty easy to do - just need a few tools and measuring devices. Make sure you have high quality parts - some of the repop stuff is junk (like all the repop transmission shafts!). If you need help, feel free to drop me a PM. Another guy that might be able to help you (if you want somebody to build one) is Dennis Lacy. He and his Pops are really great people and they are in your area:

Early V8 Garage
1217 Azusa Canyon Rd.
West Covina, CA 91790
626-338-2282

[Seth Swoboda]

You can rebuild it yourself. I did my '39 transmission myself and then the side loader for my 1940. I had VanPelts book handy and if you have any questions you can call Mac and I will talk you though them. You can do it!

[KarlJS]

Just ordered the book. Thanks guys

[KarlJS]

Down to the point to remove the main drive gear. The book almost ready like the main shaft is 2 pieces. One comes out the front with the ball bearing then the rest comes out thru the top. I was feeling so confident too.

[KarlJS]

Discovered that yes it is two pieces but mine will not split apart, any ideas on how to make one into two?

[Miles in MN]

The first step is to remove the shaft for the cluster gear to allow it to drop down into the bottom of the gearbox. With the cluster gear out of the way the main drive can be removed from the front of the gearbox after unbolting the bearing retainer (the sleeve that holds the throwout bearing collar). With the front shaft out, remove the rear bearing retainer and lock ring from the main shaft (rear) bearing and drive the bearing forward into the gearbox to remove the mainshaft with the synchro hub, intermediate gear and low/reverse slider in place on the main shaft.

[KarlJS]

The front shaft and back half will not separate, I've removed the parts that you said to. Any ideas on how to separate the two pieces?

[tubman]

I'm no expert on these transmissions, but I'll throw this out. Perhaps he has a transmission with an earlier case that had been previously rebuilt with later gears. Isn't there a "trick" about installing the main drive gear in these from the inside?

[Bob C]

If I understand what you are trying to do your answer is on page 21 of Van Pelt's book.

Bob

[rotorwrench]

After the counter shaft cluster drops down a bit, there is nothing to hold the input drive gear and main shaft together unless there is a bad bearing in there. With the front bearing and throw out sleeve support removed, the main drive gear should pull out. Sometimes you have to tap on the side of the gear with a soft face hammer while you pull. If that doesn't work, you'll need to rig up a slide hammer with some form of choker or pin puller on the front stub of the main drive gear. I've never had one that wouldn't come apart yet but there is always a first time.

[KarlJS]

Counter shaft dropped, rear bearing removed. Won't slide out the front because of syncro. Was thinking same about blocking front and using slide hammer at the rear to break it loose. Going to soak with penetrant for a few days.

[Hoop]

Karl, put down your slide-hammer, soft face hammer and anything else you might think about beating on your transmission with.

1. Count the number of teeth on the main drive gear ... the top gear, front attached to the input shaft.

2. Locate the part number cast into the lower back of the transmission case.

3. Post this information.

[rotorwrench]

The main input drive gear only meshes with the synchro hub sleeve when the sleeve is pushed forward by the shift fork. The synchro inner hub is splined to the main output shaft so it isn't physically attached to the main input drive gear. There is a hollow in the gear and a stub on the front end of the main output shaft with only a bearing between the two. If the bearing has rusted up, then there might be something to hold them together. The two shafts should rotate independently of each other when the trans is in neutral position.

I suppose there could be an oddball main input drive gear in it but it still has to come out somehow.

[35fordtn]

Why not post a picture?? If it is a 48 case and has the 29 tooth cluster with the 15 tooth main drive gear, they can be tough removing because the teeth for the Synchronizer on the main drive gear hits the cluster.. Still can easily be done.. Take Hoop's advice.. You'll tear up too much beating away on it and run a strong risk of cracking the case

[rotorwrench]

Mercury cars used the 15/29 set and possibly a few others. It also depends on whether it is a 48 case or a 78 case. The 78 was set up to use the 15/29 and has a deeper bowl down in there. A 1939 Commercial should have a 78 case but could have either the earlier or later type gears. Lots can happen in 70+ years.

[KarlJS]

Trans #18-4884434. Main shaft has 10teeth, first gear has 16 teeth

[KarlJS]

If a picture would help let me know what part(s) you would like to see

[KarlJS]

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 .

[rotorwrench]

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/F...-52-LD3spd.jpg

[KarlJS]

Rear to trans is 6 spline, front to engine is 10spline This is all new to me so please be patient

[rotorwrench]

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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.

[KarlJS]

IMG_3208.jpg
A picture of the gears, looks like a early syncro to me

[Bob C]

WOW that thing has seen better days.

Bob

[KarlJS]

Thinking rust is my main problem

[rotorwrench]

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.

[Bored&Stroked]

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

[KarlJS]

Was already looking for one. Saw one for $1200 and one for $800 both not including shipping. What would be a reasonable pice???

[Bored&Stroked]

Originally Posted by KarlJS

Was already looking for one. Saw one for $1200 and one for $800 both not including shipping. What would be a reasonable pice???

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

[KarlJS]

Thanks for looking out for the newbie.

[zzlegend]

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.

[51504bat]

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 tranny 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.

[KarlJS]

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

[rotorwrench]

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.

[Hoop]

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.

[zzlegend]

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.

[KarlJS]

Finally getting ready to reassemble the transmission. Need to know which direction the longer portion of the key (p/n 7101) points. Front or rear. Thanks