Technical Open Flathead trans to closed trans conversion

I searchded the forums and the web, but did not find anything about converting a late Flathead open trans to a tube shaft. I have an open rear flathead trans. I'm not sure of the date. I would like to install it in a car and used a drive tube, thus I need to convert the trans for a tube, or shop for another early trans. Any advise?

 

When you say "late flathead open trans", do you mean the open drive pre-'53 pickup three speeds or the post '48 car units?

 

Yuppers, this is a definite "Ya gotta give us more info than you did" deal. I've never seen a conversion for 49 and later Car transmissions to closed drive and the reason was probably that there was no market for them. If you ever had one apart you would soon figure that you would have have a complete new tail shaft/output shaft before you could do anything else.

 

I’m a rooky here with the flaty. I’m not sure how to ID a 49 ****** verses an earlier truck open trans. I will go back to the books and learn it. But just by looking at the post 48 trans, the main shaft looks longer.
I know open driveshafts are popular now. I’m just trying to build something old school.

 

It gets complicated. @Mr48chev is correct that there is no practical way to use the later model transmissions' ('49-'53 Ford and late '51-'53 Mercury cars) with a closed drive. I think just about any '42-'52 pickup 3 speed can be converted to closed drive. The only late model transmissions that can be used with the '48 and earlier engines would be the '49-early '51 Mercury units. The late model ('49-'53) engines can be used with the early ('48 and earlier) transmissions with a bellhousing and starter plate from a '49- early '51) Mercury or a '48-'52 Ford truck. The '53 pickups (while still flatheads) have a weird one year setup. Clutches are another minor problem with these. One last point; while the '49- early '51 Mercury transmissions will bolt to an early engine, they are totally incompatible with a closed driveline because of the longer output shaft and ***ociated housing.

When you decide what you have and what you want to accomplish, get back to us; there's a lot of knowledge here.

 

The 1942-50 Ford light duty 3 speed transmissions, which are the open driveshaft type, can be converted to the closed drive configuration. It means changing out the mainshaft to the closed drive type, and installing the closed drive type rear bearing retainer (which doubles as the rear support) to the type that matches your vehicle ch***is. This does involve a complete dis***embly of the transmission so it’s reasonable to plan on a basic rebuild while you are at it.

The 1951-52 versions of this transmission feature the “new design” ge****t, which cannot be converted to closed drive configuration. You could, of course, swap in a complete ge****t from a 1939-48 closed drive transmission……typically from a 1940-48 Ford p***enger car sideloader transmission. Or you can send it to us and we can do the conversion at our shop here in Cincinnati, Ohio.

 

roman, if you are new to the flathead world and all of the engine and transmission variants it might be cost effective to have Mac VP ***emble a transmission for you. You won't find a more knowledgeable and all around nice guy to work with.

 

Of course, I defer to Mac about the '51-'52 light duty truck transmissions not being able to be converted. Also, you can't go wrong having him build your transmission. He is the "go to guy" for stuff like this.

 

I'm new to Flathead Fords, but not new knuckle busting. The open drive is transmission is already rebuilt. Based on my new education, (thanks to advice above), it looks like it will be easier to acquire an earlier trans and rebuild it, than convert the old open drive to a closed drive. This is ok. I'm building two cars at the same time, both with Flatheads. One is a TROG's racer (which is the transmission that should have a tube drive) the other is a fancier road car. I guess it will get a driveshaft. I am going to buy a rebuilt kit from MacVP, (plus many more parts, the list is growing.) Thank you again.

 

Roman,

It would really helpful if you could post some pictures. Try to get a pict or read off the cast in numbers on the rear left bottom corner of the trans case and a shot of the gears with the top off.

If you can do that, we can give you a lot more information about what you've got and what can be done to it.

Banjo