M939 Front Drive Axle Confusion (sorta)

[mgman]

I have seen numerous posts about the two styles of front drive axles which are the Universal joint and ball/cv types. Posts state that the CV was replaced with the u-joint type. Here is a copy & paste from manual 9-2320-272-23-3, manual page 0411-4, pdf page 596:

"New configuration axle shafts have a CV joint in place of the universal joint. Axle shafts are
no longer repairable and must be replaced if damaged."

Soooo, which is right? Was there any issue with the u-joints? Inquiring minds want to know.

 

[G744]

The U-joints will 'kick' at full lock turns, as the ratio of in-to-out speed differs. The CV ones don't do that.

CV joints are based on the old school types of Bendix, Rezeppa, Spicer, and Tracta.

DG