I am trying to find information/specs for the original driveshaft and u-joints that would have been factory installed in my '67 RO23 4-speed car.

The original driveshaft was not with the car when I got it so I am not sure what I should be looking for. The '67 parts book shows part number 2781955, 3.00" diameter and 50.27" long, for Hemi with 4 speed and 9 3/4" axle. The RO23 broadcast sheets that I have seen show the part number "99", which decodes to "special order". I am not sure what the "special order" means.

I would appreciate any information that would help me determine the dimensions and u-joint specs for this application.

I would think it's the same shaft used in the '67 440/Hemi 4spd cars.
The one in my car is 3", has the large ring at the front and uses the Spicer U-joints (1310 or 1330, not sure which one).

Thanks for the reply. I thought the same thing, but the "special order" on the broadcast sheet made me think that something was different.

As far as I can tell, the RO/WO drivetrain was the same as the production hemi cars, except that the 4-speed cars came with a 4.88 rear axle. I don't think that the 4.88 was available as factory option, so it makes me wonder if the 4.88 gear set requires a slightly different driveshaft length.

Anybody know if this is true?

Would be interesting to see a 67 GTX or R/T Hemi 4spd buildsheet to see what number the driveshaft shows for those cars.

Wonder if it could be the same shaft part # but with stronger U-joints? Or maybe it got higher speed balancing with 4.88 gears?? Just some WAGs.

The length of the pinion will be the same no matter the ratio.

Do you have the rest of the original driveline parts? The RC 426 bellhousing, Hurst shifter, Dana with Spicer yoke and the SS springs?