2 piece driveshafts

[pishta]

ever wonder what these things looked like opened up? Just for grins, trying to determine how I could shorten this (I think it is hopeless) I cut one. first cut was over the rubber so it didnt seperate so I thumped it until I heard a hollow part and put my pipe cutter to work. I caught about 1/8 of the rubber but it came off cleany and with a little pop like a biscuit tube from the refrigerator section! The rubber insert expanded as I pulled it off, interesting..so I cut a slit on the remainder of the rubber bonded tube and walked around the bench to get something. I heard something drop and went back and found the tube had split where I scored it, and it split pretty good. Seems that rubber in there is under considerable pressure. I pried the other half off and found rings of vulcanized rubber supporting the inner shaft to the outer shaft. I guess that stuff is pretty strong as it can take more than 300 ft/lbs of torque right? Here are a few pics to file in the "stuff you dont really need to know" folder. The weld yokes are welded to flared ends of the tubes so you cant really shorten these in a standard fashion. Now how they manufacture these, good question. Does the liqued rubber expand after being injected into there and vulcanize?

 

[fishy68]

Interesting. I have never cut one open. I assume the rubber must expand after being injected. No wonder stock drive shafts are so heavy.

 

[67Dart273]

Interesting. I've seen a couple "slip" in their day, driving people nuts for awhile, because even if they don't get out of round, the U joints get "out of time" and they vibrate.

In my mind, these damn things belong the same place as nylon cam drives. --the garbage can.

 

[Bulldozer]

i had a friend of mine take 4 inches out of my driveshaft which came out of a 86 lebaron.there was that same "harmonic balancer" type of rubber and inner shaft that extended about a foot and a half in from both ends of the driveline. it did not go the whole length of the driveshaft. the only way to put it back to together would have been to weld the inner shaft to the end cap and then somehow slide it back in with the rubber around it. there was no way to do that because the rubber expanded after it was pulled out so, we had to leave the inner shaft and the rubber out and just weld the end cap back on the shaft. i had it spin balanced and new u joints put in it and it works just fine. i guess it was just a harmonic sound deadener that they used.

 

[TrailBeast]

I have been told by the shops that they do not even try to do anything with those shafts, but just build new solid tube shafts to replace the dampened ones.
Quotes were about 200 for a new built.

Interesting note,
Boat props are built kinda like that, and you should see what happens when the rubber gives in one.
It'll freak ya out from the noise and vibration.
You'll think your gearbox is trashed.

 

[Supershafts]

That is not a 2 piece shaft...

That is done for sound effects traversing to the other end of the shaft, and how you get that out is by heating the inner tube and pulling. That shaft is wrecked now