some had thicker wall tube dia . otherwise yes 1/2 and 3/4 ton use same housing and inner "C" units and knuckles . just brakes and # of lug studs .
that is a early run axle tho with flat top pass side knuckle and upper tie rod style . and the rim/tire combo looks like 37" g/y h1 hummer tires on aluminum rims . this leads me to guess 16.5 8 lug rims . so prob a 3/4 ton 8 lug axle as not many aluminum rims made for 16.5 tires in 5-6 lug .
unless for some crazy chance you can find and read the dana B.O.M # stamped in the axle tube . . . .
