if you push up and down on the truck while the wheels are on the ground, thats a suspension bushing.. just a peice of rubber, but to reallky inspect the bearing, your going to have to pop the axle out to check the bearing to see if its shot or not, that will be the best way, in my opinion

 

Thanks for the reply. I do have some experience with trucks. Maybe I wasn' t that descriptive. I didn't just bounce up and down
on the bumper to see if the bearings were bad. I rocked the tire/wheel from side to side by grabbing the top of the tire and pushing
it away from me and towards me to check for play. There seems to be a little back and forth play, kinda like a knocking sound when
I push on it Mostly on the drivers side, even when I rock the passengers side I hear it on the other side. Thanks and much appreciated.