knocking problem
 

hey guys thanks in advance for any help
i have a early 99 f250 7.3 and when i bought it, it knocked over bumps i didn't think much of it and since it didn't have any play in the tires i changed the sway bar endlinks but the problem has gotten worse it now knocks constantly while driving on smooth roads and i can feel it in the floor boards and i read online that if i have bad hubs i could damage my axle which i have the symptoms of but i dont seem to have any play in the tires any other possibilities or ways to test my hubs? i need to get my truck back up and running without damaging it.

I had the problem diagnosed as wheel hub assembly's to I changed the hubs, hub assembly's, u joints, and knuckle seal but the knocking persists:argh::argh: