1 or 2 piece driveshaft

[caferacerx]

what is the deal with the 2 piece driveshaft in a 67 dart? are they junk? keep it or find a 1 piece to have shortened? thanks for any help

 

[CHEATHAM]

I never heard of this kind of set up, im guessing someone took a tranny out of a motorhome or heavyduty truck and it has the bolt on yoke so they modded it to work in the car

 

[caferacerx]

it is the stock one out of a 67 dart GT some kind of isolator? large diameter end pressed into small diameter end

 

[JR]

Pics?

 

[pishta]

Yes, I got the same one! Normal looking driveshaft until you get to about 6" from the Diff end, then it looks like they took a 1/2" smaller tube and slid it in there and secured it somehow. There is a welded weight about 6 down from this joint. Could it be an elastomer (balancer type vulvanized rubber connection?) down in there? About 1/8 inch air gap between the 2 tubes, Maybe for harmonics, makes shortening it a pain as the tube necks down for the trans yoke only about 4" from the end.

 

[67Dart273]

What you are referring to is NOT a "two piece driveshaft." THIS: is a "two piece" driveshaft on the right, lying next to a "one piece" shaft on the left. Notice that the "one piece" shaft has a slip yoke, meaning it actually is MADE OF two pieces:

You are simply referring to the earlier Chrysler what amounts to a combination U joint and slip yoke, combined.

This was called a "ball and trunnion" or "Detroit" joint:

http://www.earlycuda.org/tech/ujoint.htm

 

[pishta]

Nope, here it is, the "other" 2 piece driveshaft:

Turns out these were common on Mustang automatics, and go bad with age, as you can see.

 

[67Dart273]

Nope, here it is, the "other" 2 piece driveshaft:

Turns out these were common on Mustang automatics, and go bad with age, as you can see.

Oh, poop. I was lookin' at his avatar, not thinkin' he said '67

Technically, that is still a "one piece" shaft.

The BIG problem with those (rubber molded inside) is that WHEN THEY SLIP (and they will) the U joints get "out of time" and cause vibration. Another Detroit "great idea" just like the (junk) fiber timing sprockets, "for noise." Yep. They're more quiet, OK, when they quit.

 

[Inertia]

Yep, had rubber sleeve in there,anti-vibration, and they twisted THEN,, that rubbers 30 yrs older now, but they twist real easy

 

[Supershafts]

That is not a 2 piece shaft, what 67 originally shown you was correct.

that wasn't a detroit idea, that was saginaw.

detroit does it inside the shaft, when you cut apart the factory shaft there will be a rubber and inner tube in there

upgrade it to the pic of the shaft on the right in 67's comparison picture