Im currently in the process of building a chassis for my coupe project. I have the running gear installed and now on the job of shortening the solid type drive shaft for the closed drive running gear. Torque tube was a breeze but im second guessing the driveshaft length, trying to decide just how much of the drive shaft protrudes through the UJ .. OR, same question, what kind of distance is there between the snap ring and the back edge of the UJ OR put another way ,does the snap ring sit hard against the speedometer drive. Either answer would give me the setting point for the front section of the drive shaft within the torque tube .. Im pretty sure I have the matching drive shaft for the torque tube as the front bearing and center bearing are running perfectly on the appropriate machined surfaces of the driveshaft, but there is a bit of wiggle room back or forward to set the shaft in the best position. Im not sure its 100% critical but if its in the region of Fords tolerances then its all good an I can go on and chop the shaft to the correct length. looking forward to any input..
Shorten the drive shaft the same dimension as you shorten the enclosed housing. Should be good! Bones
What bones said. Take the same out of the shaft as you did the torque tube. Everything will line back up again.
problem with that is that the Torque tube came to me with a chunk off the rear, the rear section came from another torque tube. The shaft is a fluke, in that the front and center bearing line up. It was in the garage rafters .. one of 3, one chopped up, one far to long with bearing runners in different locations to the TT and one that seems to be the one matching the remains of the TT .. PLUS an end from the scrap bin.. from a completely different source.. Unfortunately no starting measurement otherwise it would have been easy .. should have mentioned, this is being built for buttons from cast offs and other folks junk, and a healthy dose of home fabrication, old school style
Do you have your speed-o-meter gear housing bolted on? It limits were the solid drive shaft can set forward to aft. If you rest the solid drive shaft in the center of your speed-o-meter gear play, front to back, I think you will be just right. I know what you are asking for, but I cant see how far the shaft in protruding through the U-joint when it is all bolted together.
Ok, we see your problem. Sold my last rear end/ tube/driveshaft, so I can’t help you. But I bet they’re others that have one lying around that they could measure. Bones
On where the front bits go...the answer is built in: With speedo drive and the stuff associated with that, the snap ring, gear, thrust washer, roller bearing and its seal, all put in place on the shaft/in the torque tube, all is located when all is together and bottomed out against the seal in the torque tube. THAT locates everything in front, and the U joint is entirely located* when bottomed out bolted to the output shaft of trans*. U-joint doesn't actually care about the other stuff! The measurement needed is at the rear of the shaft...it needs to be located so it connects through the splined tube to the pinion gear with holes lined up for the connecting pins. I think close measurement not very important here...you want the shaft mostly in the splined tube but not butted up against pinion. Probably sane approach is to get it assembled and then drill shaft through the pin holes in sleeve...with the front stuff in correct place, of course. Go to THIS Van pelt page and look at the front end assembly down near the bottom of page http://www.vanpeltsales.com/FH_web/FH_images/FH_rearend-pics/ford-rearend-32-48-A.jpg *On the loction of U-Joint: U joint is bolted solidly to trans output shaft by tightening the bolt at its center...but BEFORE tightening it down carefully study the rear of the gearset. The rear bearing must be tucked into the hole at rear of trans casting all the way and stopped/located by the snap ring around front of bearing. This locates the innards of the trans as well as the bearing, and locked into place by the U joint. A screwup here potentially leaves gear train floating. Note from Ford picture linked above that rear of u_joint can't even reach the other stuff discussed here because it runs out of splines!
Cool. I had the speedo stuff orientated correctly .. thhat was the easy bit lol. The assembly pushed all the way in makes send as it secures the speedo drive gear in one location within the window to contact the speedometer drive .. With respect I dont think that bottoming out the rear end is an issue since it is usually hard pinned with zero movement, any movement being at the UJ end. In this application the spline coupler will be welded to the chopped shaft .. Basically so long as the front of the shaft doesn't protrude so far through the UJ it prevents the UJ from flexing or bottoms out on the UJ securing bolt, or falls out the end due to insuficient spline contact , it should be good ... The measurement im after is basically the position of the front tip of the drive shaft compared with the top edge of the torque tube cup. Just as you have visualised Bones BUT as you say Bruce, that measurement is predetermined by assembling the speedo gear and associated components into the Torque Tube .. the snap ring will stop the shaft, and the subsequent measurement for the working length of the shaft taken from there .. That answers my question or at least reassures me things will be in the ball park , wont bind up, fall out or f**k up prematurely .. Up until now ive been guessing .. and putting off ... But I think I can say im now reasured .. cheers
Thank you for the additional info Bruce . Got that part covered . The gearbox is actually a Volvo 4 speed with a closed drive conversion and bolted to the flathead hogs head . One thing here to note is that the volvo input shaft shares the same clutch spline as the 9 1/2 inch 8BA clutch.. Went to the garage earlier, built up the parts into the torque tube pulled it all the way back and measured up for the cut . Im my case 1240 mm from the front tip of the drive shaft to the cut mark .. Its a little longer than most folks might be since, as mentioned earlier, this car is being built from the junk in the shed .. The rear end was worn out but I had a 48 axle that was complete but a little to wide for the coupe . The other issue was that the pinion spline had been docked when the rear end was crudely liberated from the donor at some point in history .. The upshot was that it was missing roughly an inch and a wee bit of the spline.. The good thing was that it was a decent ratio ( 3:78) and had minamal wear, so the axle built up fine within tolerance. There is still plenty spline on the pinion shaft for the coupler, I just had to bump it up a little further and drill a new pin hole.. Will turn the shaft down on Tuesday and proceed in joining the front bits to the rear bits.. Thanks for the input, it was just one of those uncertainties I was procrastinating over, all sorted now. Many thanks..
I just went through a similar situation like this. I had a torque tube fit to my car, but didn't have the correct inner drive shaft to match it and shorten accordingly. I took the banjo section with the pinion gear assembly installed, and installed a driveshaft and torquetube that I knew was a factory match and assembled it to my banjo. At the bell end of the torquetube I measured the distance of the driveshaft compared to the bell end, it was .110 below the end of the bell. Next I went to look at another rear axle assembly that was never disassembled, I measured it at .120, so at hat point I felt I had a good measurement. That's what I used for my shaft.
I have noticed that too, even up through the 70's..I used to make a lot of deep sump oil pans gas welding them together.. The Chevies were horrible, Mopars way better but the Fords were heaven...
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