'35 Model 51 Transmission Removal
 

After 90 years of service, the transmission gave up today and will need to be removed for repair. Is it possible, or practical, to remove it to the rear leaving the engine in place, or should I just pull the engine and go out the front? I've never worked with a closed driveshaft before.
Thanks in advance.

Re: '35 Model 51 Transmission Removal
 

Excellent question - the answer depends on your experience, skill level, and how well-equipped you are. I think it's less work to pull the rear axle especially if you have a lift.

Re: '35 Model 51 Transmission Removal
 

Not sure but isn't the cross member in the way to remove the transmission to the rear?

Re: '35 Model 51 Transmission Removal
 

Here's an excellent article that should give you all the info you need to remove the tranny without removing the engine...

http://vanpeltsales.com/FH_web/flath...ns-removal.htm

Re: '35 Model 51 Transmission Removal
 

The Model 51 is a big truck with 4-speed.

Re: '35 Model 51 Transmission Removal
 

Need to remove the rear axle and then the floor mat and floor,, the trans comes out thrugh the inside

Re: '35 Model 51 Transmission Removal
 

Thanks everyone so far.
Bob C is correct; it's the big truck in my avatar. The cross member is bolted in and should come out. I'd have to look to see what it would take to move the rear axle back. The engine was out a few years ago so pulling it doesn't concern me other than the work involved. I was just checking to see if there were any alternative ways of getting it out.
Keep the ideas coming. Thank you.

Re: '35 Model 51 Transmission Removal
 

You should be able to remove the coupling shaft without removing the rear axle. Pull the coupling shaft front cover back and unbolt the back part of the u-joint and you should be able to drop the coupling shaft.

Re: '35 Model 51 Transmission Removal
 

Re: '35 Model 51 Transmission Removal
 

Thank you for the additional information. Would the coupling shaft shown be the same in a "35?
The truck is three hours away, so this is going to be a little drawn out. I'm sure I'll have more questions. As always, many Thanks.

Re: '35 Model 51 Transmission Removal
 

I have a 1932 coupling shaft on the bench right now and it looks just like the one in the picture so I'd say the 1935 should be the same.

Re: '35 Model 51 Transmission Removal
 

KDL - Do you have a copy of my book? It includes all the pictures and information you need to remove the transmission.
The coupling shaft can be disconnected from the rear of the transmission because the universal joint can be parted. It has screws which hold the flanges together. Just slide back the front part of the coupling shaft cover (made of sheet metal) and it will expose the differential. It should have the bolt heads wired together. Once the coupling shaft drops out then support the engine weight. You can then unbolt the cross-member holding the end of the engine-transmission assembly. Then the transmission can be dropped out. There are lots of details of parts and pieces that need to be unhooked or gotten out of the way, but that's the general idea. Ford designed the truck this way just for this purpose. You can also inspect your clutch and flywheel and make and repairs or replacements while you have the transmission out.
Feel free to PM me if you want more information.

Re: '35 Model 51 Transmission Removal
 

Bob, Thank you for the clarification.
David, Yes, I do have your book! I’ll be studying it the first chance I get. I tried attaching a video of the transmission but it won’t accept the file.
More questions to follow I’m sure.
Picture is from the 4th of July when she was still moving on her own.





Attachment 570449

Re: '35 Model 51 Transmission Removal
 

[QUOTE=KDL;2401882]Bob, Thank you for the clarification.
David, Yes, I do have your book! I’ll be studying it the first chance I get. I tried attaching a video of the transmission but it won’t accept the file.
More questions to follow I’m sure.
Picture is from the 4th of July when she was still moving on her own./QUOTE]
https://www.fordbarn.com/forum/attac...9&d=1753207777

Re: '35 Model 51 Transmission Removal
 

The transmission came out over the weekend. No surprises on the removal. We were able to cradle the engine with a ratchet strap around the frame rails so we could still move the truck around. Other than the transmission problems, we did find the rear u-joint of the Coupling shaft had been running dry. That will have to be looked at.
Attachment 571220

Attachment 571221

Attachment 571222
Will Vanpelt be my best source for transmission parts? Any others suppliers?

Re: '35 Model 51 Transmission Removal
 

Fred at [email protected] has NOS parts.
What parts do you need?

Re: '35 Model 51 Transmission Removal
 

I haven't pulled it apart yet, but I'll probably need bearings, gaskets and a main shaft for starters.

Re: '35 Model 51 Transmission Removal
 

https://www.fordbarn.com/forum/attac...0&d=1754303704

https://www.fordbarn.com/forum/attac...1&d=1754303603

https://www.fordbarn.com/forum/attac...2&d=1754303704

Re: '35 Model 51 Transmission Removal
 

Rear bearing.

Attachment 571232

Re: '35 Model 51 Transmission Removal
 

[QUOTE=KDL;2404266]Rear bearing.

https://www.fordbarn.com/forum/attac...2&d=1754336392

Re: '35 Model 51 Transmission Removal
 

Wow, that's unusual. The 4 speed transmissions are typically near indestructible. These 4 speed non synchro (crash box) transmissions have little to no value, I have been given and given away several of these over the years. Maybe look around locally to see if anyone is giving one away that you could get gears from if needed? I agree, I would put bearings and gaskets in at a minimum.
Is it the original transmission to the truck? If yes it should have the serial number of the truck stamped into the flat area above the throw out bearing inspection hole.

Re: '35 Model 51 Transmission Removal
 

The problems originally started about a year ago. It would act up every once in a while. A few small pieces were found floating around, never a good sign, but we were not able to identify where they came from. A good cleaning and new gear oil and it ran and shifted fine, for a year, until it didn't. But, even with the bad rear bearing and broken main shaft, she still drove home under her own power, truly amazing. As far as I know, it is the original transmission, *BBT8-T8 13947*
If anyone has a spare 4 speed taking up space they want to part with, let me know.
Thanks

Re: '35 Model 51 Transmission Removal
 

New bearings by Timpkin are still available for the input and output shafts. There are also two roller bearings on an internal shaft. Those come up NOS now and then and you can also check with the old Ford parts suppliers.

Clean and inspect the gears carefully. These transmissions are normally very bullet proof and reliable. Hopefully you can figure out what happened to yours.
I have some used gear parts if you need something.

Lubrication of the differentials is important and maybe the prior owner overlooked proper maintenance. To inspect and clean the rear differential you will have to drop the driveshaft which you can do without removing the rear axle.

Let me know how things go and I can guide you if you need help.

Re: '35 Model 51 Transmission Removal
 

David,
I hope to put together a list of the parts I need, and a list of parts that would be nice to change, all depending on cost and availability.
I'll send you my list, maybe you will have something I can use.
Thank you for your offer of guidance. It is very much appreciated and will most likely be used.

Re: '35 Model 51 Transmission Removal
 

The serial number is more likely *BB18-18?13947* There short section in the front of the book which shows the serial number layout and a table in the front of the book showing the serial number by month of engine-transmission production dates. There's a number between 18 and 13947 but maybe it got stamped very lightly.

Re: '35 Model 51 Transmission Removal
 

You are correct! Looks like the Number is 1843947, April 1935.


Attachment 571290

Re: '35 Model 51 Transmission Removal
 

[QUOTE=KDL;2404561]You are correct! Looks like the Number is 1843947, April 1935. /QUOTE]
https://www.fordbarn.com/forum/attac...0&d=1754488101

Re: '35 Model 51 Transmission Removal
 

Good deal.

Mac VanPelt is my go-to guy for transmission questions and parts. I'm happy to look in my boneyard for any truck transmission parts you may need, just let me know.

I'm also very curious to know what caused your transmission to fail. Keep us posted on any discoveries.

Re: '35 Model 51 Transmission Removal
 

David, PM sent.

Re: '35 Model 51 Transmission Removal
 

Attachment 575949Finally got back to the transmission today. No big surprises. Main shaft snout broken, rear main bearing shot. Rest looks good. Lower shaft feels tight and rotates smoothly. I’m leaning towards leaving the lower cluster and original roller bearings in place verses replacing with new bearings. Thoughts on that? Thanks to Mac VanPelt and David G for hooking me up with the parts I need.

Re: '35 Model 51 Transmission Removal
 

You may have already done this, but I'd take the lower shaft and bearing out just to give them a good cleaning and then re-use them.

Did you find a replacement main shaft? I may have a spare if you didn't.

Re: '35 Model 51 Transmission Removal
 

Re: '35 Model 51 Transmission Removal
 

Yes, I was able to find a NOS main shaft.

Re: '35 Model 51 Transmission Removal
 

I have every part as far as I know of. NOS mostly from the now defunct Joblot automotive, back in the 90s, some parts from Bob Selzam's Half Ton Fun in NJ. Shafts, bearings, gears, all. They are in boxes in an unheated attic above my woodshop. Last time I looked they were nice. I only have one t-9 truck left and it gets maybe 100 miles per year. Make you a good deal. Will get pics tomorrow. It's flashlight and ladder territory.

Re: '35 Model 51 Transmission Removal
 

If the end of the main shaft broke off, I would guess the bearing surface of the input shaft that that nub rides in is bad too. Besides cleaning, removal of the cluster gear would allow inspection of the bearing surface inside the gear, and condition of the thrust washers on either end. Do it all while you'er in there.

Re: '35 Model 51 Transmission Removal
 

KDL I have a good free transmission if you have a way of getting it to you .
Gary

Re: '35 Model 51 Transmission Removal
 

Thanks everyone for the input. I will pull the lower shaft for a better inspection of the bearings. The front input shaft bearing area looks good. Surprisingly, even the bearing looked undamaged despite the broken shaft. With the exception of a spacer and an oil baffle, the only other part I need is the rear bearing retainer, #BB 7085. I was able to get a good useable on from David that I will use unless I can find a better one.
Date stamp on gears proves they are original. It really amazes me how a gearbox this old can still look so good.
Attachment 575975

Attachment 575976

Re: '35 Model 51 Transmission Removal
 

https://www.fordbarn.com/forum/attac...5&d=1761422066

https://www.fordbarn.com/forum/attac...6&d=1761422066

Re: '35 Model 51 Transmission Removal
 

GB, I think I'll be good with the parts I have but I'd be interested in what you might have for a T8, just in case. Please don't go through too much trouble.
Ggmac, PM sent.