F 250 and F150 shafts?

[andyxj]

Are late 70's model Ford F-250 and F-150 shafts interchangeable, the only difference being lug pattern? (say 76-79)

 

[Sierra Drifter]

Are late 70's model Ford F-250 and F-150 shafts interchangeable, the only difference being lug pattern? (say 76-79)

Assuming you are refering to the D44 front axle:

They are not interchangeable.
Diameters are the same.
Outers are the same.

1978 F250
inner long shaft 34 3/4" 1 5/16" dia. 30 spline
inner short shaft 18 5/8"
outers stub shafts 9 23/32"

1978 F150
inner long shaft 33 29/32"
inner short shaft 18 29/32"
outer stub shafts 9 23/32" 1 1/4" dia. 19 spline.

The exception would be the F150 SuperCab which has the same shafts as the F250. F250 is 8lug 8 by 6.5. The F150 is 5 lug.