2000 Gran Caravan Rear Drums

I have a 2000 Gran Caravan with "15 standard wheels, I need to know if this problem is normal or not. Without untighting the lug nuts, I raised the rear passenger-side wheel and rolled it forwards and backwards noticing a knocking sound everytime I changed direction. I retighten the lug nuts (95 ft-lbs) to make sure they were on. Further inspection revealed play between the wheel and rear drum (as I slowly turn the wheel in one direction the drum follows a second or two later).
I took off the wheel and drum and inspected these parts including the Hub/Bearing assy and the lugs bolts. Found nothing. I thought I was missing a part so I inspected the Drivers-side rear wheel to find it has the same knocking noise as well. Anybody experienced or have noticed this before?

Hatcho21

If you turn your wheel, the drum should turn.

Thirty years ago I had a problem as you describe. That turned out to be the wheel studs wearing an elongated hole in the drum. The tire rim used was improper for the car. The center hole in the tire rim did not fit completely over the center hub and failed to seat properly. Each time the brakes were applied, a clunking noise was heard and the studs wore sideways into the drum.

You were right! I bought and installed new brake drums and brake pads and the knocking noise is gone. A friend of mine noticed that the old drums were OEM. I Appreciate the help!