Driveshaft lento

[steve from staten island]

1969 B body with 727 trans and a 8 1/4 rear. Would the same car. with a 8 3/4 rear have a longer driveshaft?

LOL...Length not lento

 

[Lefty71]

Guessing, but shorter for sure i would think.

 

[kramer]

1969 B body with 727 trans and a 8 1/4 rear. Would the same car. with a 8 3/4 rear have a longer driveshaft?

LOL...Length not lento

It looks like according to this tech archive on Moparts that the driveshaft would most likely be a little over 5/8 shorter with the 8 3/4 axle since the yoke centerline to axle centerline is longer on the 8 3/4 by over 5/8's of an inch.
http://www.moparts.org/Tech/Archive/axle/5.html

 

[steve from staten island]

Now im really confused as I thought I needed to lengthen the shaft. With the shaft pushed all the way into the trans I had 1 1/2" between the center of the universal to the center of were the u joint fits on the differential yoke. I was told 3/4 max. Also with the original shaft from the 8 1/4 now trying it with the 8 3/4 rear I felt there was not enough front yoke spline in the trans.
I had a shaft made and I must have screwed up as the shaft is to long and wont fit. Im going back to the guy tomorrow. I measured exactly the way he told me

 

[Fran Blacker]

The weight of the car is on rear suspension and not hanging when you tried that driveshaft?

 

[steve from staten island]

The weight of the car is on rear suspension and not hanging when you tried that driveshaft?

I measured it wrong Fran

 

[Lefty71]

I measured it wrong Fran

Too long is a better situation than too short. At least you still have something to work with to repair it, as opposed to buying another and selling one that no one needs.

 

[steve from staten island]

I can't believe how I F-ed this up. I have to have shaft shortened and then rebalanced. Well a lesson learned,im sure its a hundred dollar bill but at this stage of the game LOL

 

[steve from staten island]

Just got in from garage. I put weight of car on springs and remeasured. It looks like the original shaft length would have worked.
The differential yoke was worn and had to be replaced anyway. I know now what happened and I'm bringing shaft there this afternoon.
The good thing is this shop works fast and I may have it back later on Monday or Tuesday at the latest.
Im just glad shaft was to long rather than to short.
Thanks for the help!!!!!!!

 

[Cranky]

One way to avoid spending more than needed is to trial fit stuff like that. Had more than one car where a drive shaft actually fit better after a rear end change.....