What is the difference between a torque tube and a drive shaft.?I saw a vid on Youtube where this guy found a sweet 41 Buick and mentioned it was going to cost him a lot of money to have the clutch changed because it had a torque tube.What would cause this problem and what was the perceived advantage of the torque tube design?
The torque tube ties the back of the transmission to the rear end. Rather than a drive shaft with a U joint at each end the torque tube articulates on a spherical deal at the rear of the transmission. As well as connecting the driveline components the torque tube also acts as a location member for the rear end. There are plenty of threads on the HAMB about failures of rear wishbones on early Fords that have been converted to open driveshafts. Roo
Torque tube set up looks like this on a 41 Ford. This is a typical example of a torque tube set up. Ford used the torque tube design as it allowed the use of only a transverse spring with the outer torque tube and V-shaped radius rods used to hold the rear end in place so it wouldn't move sideways. The torque tube also absorbed lots of torque and prevented rotation of the rear end as it is bolted to the banjo. That's why folks who do away with the torque tube and install an open drive line often install a torque arm since the radius rods can't handle the load and will fracture over time. The problem with the torque tube design is that you had to literally remove the entire driveline to change the transmission unless you removed the engine. Also, there is only one universal joint ( hidden under a clamshell housing behind the transmission) so you couldn't remove just the driveshaft or transmission by itself without sliding the rear end back from under the car so you could remove the torque tube itself. In short, you could not remove the driveshaft or the rear end as a single unit. Unlike today, with a torque tube design, there is lots of labor and time involved to install a flywheel, pressure plate/ clutch or transmission if you didn't want to remove the engine. 1st photo shows outer torque tube that slides over the solid steel drive shaft. Left end attaches to transmission. Right end attaches to rear end. Radius rods (V shaped) bolt to each end of rear end assembly behind backing plates. 2nd photo shows actual solid steel drive shaft with torque tube removed. 3rd photo shows assembled torque tube and drive shaft as removed from car. 4th photo shows how torque tube (on right) bolts to the rear end banjo housing. 5th photo and 6th photos shows where rear radius rod attaches to rear axle housing to stabilize it. PS: I am not a rear end expert so qualified engineers or builders may offer more detailed answers.
I cannot speak for a Ford torque tube assembly, but a Chevrolet transmission can be removed, from the Chevy torque tube vehicle, without removing the entire driveline or engine. "The problem with the torque tube design is that you had to literally remove the entire driveline to change the transmission unless you removed the engine. "
Very good job 19. I never did understand the torque tube drive as I am a 50's, 60's guy. At least now I have an idea of the concept. Looks like a real PITA to have to deal with. Thanks again for the explanation and the photos were a great help.
Back in the 60's we had a 55 Buick drag car with a 365 C.I. 1958 Roadmaster engine and 37 Buick floor shift transmission and a torque tube. I've replaced so many of its clutches and transmissions I believe I could still do it almost blindfolded. Once you disconnect the coil springs, radius rods, shocks, parking brake cable and the torque tube to transmission bolts you simply roll the rear wheels aft to disconnect the torque tube from the transmission. Its not that big of a deal. The rest of the clutch or transmission replacement process is the same as any other. Gary
Not really. Probably does not take more than an extra hour to remove the tranny. For those that do not know, the Buick drive shaft inside the torque tube is hollow, like an open drive shaft. Ben
There's a good description of how a torque tube drive works on www.NashRamblerRubber.com . They make the torque tube trunnion stabilizer for Rambler and Nash but the drive works the same for all cars that use it. Lexus LF-A, Miata MX-5, Corvette C-5, C-6, Porsche 928 & 944 etc. Because of the rear coil springs, torque is transmitted through the outer covered drive shaft, through the transmission case and engine block and the body of the automobile is pulled by the motor mounts. You need good front motor mounts and a good trunnion stabilizer to stop the torque tube wondering around. That keeps the rear wheels from steering the car.
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