Thread: split or one piece drive shaft?

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I,m working on a 46 chevy pick-up, slipping in a V8 with auto trans and new diff.and was wondering how long you can go with the drive shaft before going to a split shaft, or doesn't length have anything to do with one piece or split?Thanks

I've seen some pretty long shafts on commercial trucks in the 2T to 5T range, some as long as, perhaps, 10 feet, or maybe more; I've also seen more two piece shafts on that type of truck than one piece. One way to look at it is in terms of maintenance: For your application, a one piece shaft with a transmission slip yoke will be the easiest to maintain; no mid bearing alignment, two less U-joints or CV joints to take care of, easier to balance, etc. Depending on the layout of your truck, the shaft will be somewhere between four and five feet long, pretty much a regular old "as we know them" driveshaft. In my estimation, anything more would just be overkill. Of course, length isn't the only reason for using a two piece driveshaft; Other things may come into play, such as chassis design and configuration, where a crossmember would interfere with the shaft movement. Another thing to consider is that the longer a shaft is, the easier it will be on U-joint bearings, because the joint angles in the wider arc of travel will be less acute, probably a small factor in the larger scheme of things, though.

Thanks, I really don't want to use a split shaft. I'm using a truck arm set-up from the late 60's early 70's chevy truck which means the shaft needs to go through the cross member but that shouldn't be a problem because with that long a shaft I don't see a lot of travel. thanks again

Originally Posted by mitchell.adams

Thanks, I really don't want to use a split shaft. I'm using a truck arm set-up from the late 60's early 70's chevy truck which means the shaft needs to go through the cross member but that shouldn't be a problem because with that long a shaft I don't see a lot of travel. thanks again

Not sure about the trucks but the full size chevy cars of that period had carrier bearings in that center X. You may be able to drive without rubbing, but will you be able to raise it with a four point lift when the suspension droops? I don't think I would run a single shaft through the constraint of a stock frame without a lot of mockup and checking for full travel clearances.

I realy don't know the answer to your Question BUT I do know there is a length you can't go past. To long the shaft will have a wipping effect even if balanced. Check with a driveshaft place I know this because I had this problem several years ago. The length is shorter than you would think.