Measuring for new driveshaft - not fully loaded car (rolling chassis only)

[MoparLeo]

Here is the factory drive shaft specs for 69-76, all car models, engines, transmissions, differentials.
If everything is in the factory location these numbers should be enough. There is more than one reason that the input of the shaft goes in and out during suspension travel. They have to have a design spec to publish but the cars were never built to "blue print" specs

 

[66Satellite47]

True that cup diameter makes little difference. What I'm trying to get across is don't order a d shaft C to C unless you have the yoke your using. On my d shaft he yoke forward to where the hub starts was at least a 1/2 to 5/8 in longer than the one that I had. If I had a picture it would be plain as day.

Not sure if you mean that the overall length of the slip yoke may be different. I totally agree with that. I've had a variety of slip yokes that have big difference in the length that slides into the tailshaft. I've had 2 maybe 3 different overall length OEM Mopar slip yokes and at least 3 aftermarket slip yokes of somewhat different overall lengths. That includes the variety of U joint sizes from 7260, 7290, 1330 & 1350. The drive shaft length is defined by the center to center distance between the slip yoke and the rear yoke.

 

[Thunderlugs]

I guess you answered your own question is post # 14. The solution is to simply re arrange your assembly schedule. I just went through this with my 65 Belvedere. Just short of completion, I added some ballast to simulate what was missing, (simple math) and jacked up the car, set each corner on spare wheels which gave me 6 inches more of ground clearence, did my measuring, and had a new shaft made inside of a week. Then did my exhaust at the end.
This is just the way I dealt with my somewhat simular situation.

 

[Kern Dog]

I talked with Strange Engineering this morning & they provided me with no help as to whether the distance increased or decreased with a fully loaded car.... they just said it "changes based on weight."

I checked my car last week. I had the EXACT same measurement with the axle hanging as with the car weight on the jackstands.

 

[MoparLeo]

Does the post # 24 car have airshocks ? Hard to tell. If so and there is air in them, of course the length will be the same. The car can't sit down to stock height.