The Stovebolt Site Forums The Shop Area Engine Shop Torque tube overdrive??

My Dad had a 50 Chevy with a add on overdrive that went behind the trans, after shortening the tube. Has anyone heard of such a thing? Where might I get some info on it? He had removed it before trading off the Chev and stashed it away. I haven't found any name or tag on it yet. I think I have all the hard parts for it and the 4.11 rear that he had behind it.
Thanks for any help.
Raycr

I have heard of this before but have no info about it. I would like to know more too. Maybe somebody else will jump in. Keep us informed if you learn more.
Oh, btw, Welcome! :p

I've seen that done before on a torque tube where they spliced in the overdrive right before the rear end. I think it was a borg warner o.d.
Not the whole trans, just the o.d. section.
They welded a small sprocket to each end where
the drive shaft was cut and butted them together
and wrapped roller chain around them. It left
a small amount of play so the joint would not snap under torque. Looked pretty neat.
I saw a short article on this in the book
"How to Restore Your Chevy Pickup" (I think that was the book) There is a company in the midwest somewhere that does this conversion.
I am just going by memory and may have missed a
few details. I'm sure a lot of other bolters have this book and may have more to say about it.

Gear Vendors says they can make a torque-tube overdrive unit. Hold your breath when you find out the price (over $3000, I bet).

I saw a 41 Chevy car for sale once that supposedly had O.D. I did not look under there to see, or drive it.
I know that Gear Vendors makes a over/under drive unit for the SM-420 but I don't know anything about a torque-tube application. And yes, what they sell is about $3K.

Truckstell of Portland, Oregon made an overdrive for torque tube Chevies. You can do a search for it in the archives.

Raycr
Was that a 50 truck? Half-ton? Probably with torque-tube - but the front driveshaft of a 50 3/4-ton is t-tube, the back half open. I know, I got one. Tell us more.

Frank50 - just curious - is that 3/4 ton drive shaft the same overall length as one for a 1/2 ton or is it longer?

Both shafts together are longer than 1/2 ton. The front shaft has the ball/socket joint on the front where it hooks up to the trans. and has the carrier bearing at the other end. Past that is an open yoke for a conventional U-joint. There is a seal in there right ahead of the yoke. Mine leaks. The rear shaft is rather short with yokes on both ends. I searched the internet and found some info about the Truckstell OD - apparently available from about 40 - 48 in cars. Maybe someone knows more???

The overdrive was in a sedan as I recall. The unit was spliced in just behind the trans and the ball went in front of it and it clamped onto the tube and moved with the tube. I had found some papers for it years ago but can't find them now.
Thanks

Probably a Truckstell OD.
You are a lucky man. That´s what a lot of guys want.
Kind of the "Holey Grail" of torquetubers

Can pictures be posted? I'll try to get some shots of the colection of parts I've found for this on here.
If this OD was for a car will if fit the pick ups with the tube?

The Truxtell O.D. was great, I saw several of them back in the '50's. A friend had one that in 2nd overdrive would do about 80 M.P.H. They bolt onto the back of the trans. where the torque tube fits, then has a back side the same as the trans. All you have to do is shorten the torque tube the same amount as the length of the unit, and bolt it on. It is shifted by another shift lever. If you have one keep it, they are extremely rare these days.