The Stovebolt Site Forums The Shop Area Engine Shop torque tube - what's so bad about?

since corvette and other modern vehicles are using them, why change ours? and this explanation left me scratching me head. translation needed

"Hotchkiss drive transfers the torque of the output shaft to the differential. No wheel drive thrust is sent to the drive shaft.........The torque tube drive shaft is used if the drive shaft has to carry the wheel drive thrust. Drive thrust is sent through the torque tube to the torque ball, to transmission, to engine and finally, to the frame through the engine mounts. That is, the car is pushed forward by the torque tube pressing on the engine."

doesn't the hotchkiss do the same pushing but without the tube? it's all connected except there's no tube connection from diff housing to trans housing. how is one pushing the vehicle forward but the other isn't?

http://www.innerauto.com/Automotive_Systems/Drive_Train/Drive_Shaft/

There are a lot of advantages to the enclosed drive shaft.

People often want to change from the enclosed drive shaft because there are very few options for changing the rear-end ratio.

Tim

tc - more, more

advantages?

few options? instead of swapping the carrier and all with a 3.90, can i just change the 4.11 r&p with a 3.90 r&p?

and, isn't there a 'creative' way to treat the rear of the tt trans case to leave it open?

http://en.wikipedia.org/wiki/Torque_tube

Others will have to provide information about other conversions; however, the only conversions that I know about (that retain the torque-tube) is to replace a 47-53 4.11 rear-end with a 1954 3.90 rear end; or, replace the 4.11/3.90 rear-end's ring-and-pinion with a 3.55 ring-and-pinion (the 3.90 would also need the earlier ring-gear's carrier).

Tim

so, the 3.90 r&p doesn't have the same bolt pattern/ring size and pinion as the 4.11?

That is mostly correct - the ring gears have different bolt patterns. The 3.55 ring and pinion kit from Patrick's is made for the 47-53 ring-gear carrier.

Tim

i get, and just got it from patrick's. now he's a gabster. and as you said, the carriers are the conflicting partners. so, now it's back to the drawing board

Rednate,

Please post up when have the kit installation complete and let us know how the conversion went for you. This will likely be my next step after I finish my 235 this winter and I want to know how it works for ya.Thanks,

Hank

hd - will do. i'll post the whole process/specs. my 235 is in the shop as we speak, and may be finished tomorrow. but i'm still caught on the open, '55, 3.90r&p/carrier swap w/od trans

Search on 3:55 and you will find a large number of posts.

SWEET has nicely chronicled his 3:55 conversion. Follow the link_s in his posts. I used SWEET's write-up and photos to guide my 3:55 conversion. It was quite helpful (thanks, Chris).

Tim

Aside from the stuff mentioned above, going from a 60 year old transmission, drive shaft and differential to a much lower mileage correctly geared combination, you're going to save a sizeable chunk of change and eliminate a bunch of headaches.

However, if you're experienced and equipped to rebuild and set up a new R&P and want to keep your truck "stock", then maybe the various "kits" and their expense might be just the ticket.

Personally, I looked at the cost and what I'd have in the end and chose to go open. With the modern T5 transmission available for $150.-$200. and diffs, with good road gearing for $100. it just didn't make much sense to buy a bunch of high priced parts and go through all the hassle. My hats off to those that do and who can depend on their vehicle getting to and from the barn reliably.

Dave

I am new to the AD trucks but I do know a big selling point for me to convert was the cost of brake parts! I'm switching to a 9"
Ford, for cheap brake parts (fraction of AD parts) and I can
change gears easy enough if I wish. It'll handle horsepower increase if the 235 dies and I swap in a V8.