Automotive
the 3rd member has a casting, and the 741 gets a lower rating because it has a 1.375 rear pinon bearing
the 742 has 1 3/4
the 489 has 1 7/8
Since all Mopar 8 3/4 use the same diameter pinion U joint flange hole (either coarse or fine spline.) The weakest link if there is one is the same spot for all three.
But, there isn't much of a weak spot, the hemi was using the 8 3/4 so, that's pretty damn good.
http://www.jalopyjournal.com/forum/threads/dodge-8-3-4-strenth.458086/
the 742 has 1 3/4
the 489 has 1 7/8
Since all Mopar 8 3/4 use the same diameter pinion U joint flange hole (either coarse or fine spline.) The weakest link if there is one is the same spot for all three.
But, there isn't much of a weak spot, the hemi was using the 8 3/4 so, that's pretty damn good.
http://www.jalopyjournal.com/forum/threads/dodge-8-3-4-strenth.458086/
