The axle on the 50's model GMC looks suspiciously like a military banjo axle.

http://g503.com/forums/viewtopic.php?f=25&t=225923

Do you know the provenance of that thruck...is it really a NAPCO, or did someone make a civy/GI hybrid?

Yes the "weird split axles" are the Timkens. I don't know all of the history on the Timken company, but those front drive axles appeared on various brands of trucks in the 30's.

http://vehiclesofvictory.com/gmc-g508/specifications/


1941 Chevy 1 1/2-ton WW2 4x4 dump truck
In the Stovebolt Gallery
Lots more pictures