I took the dryer apart. (You Tube video). The issue was a portion of the tension belt pulley wheel had broken off. The drum belt which wraps around the drum and the pulley would make the drum spin off balance, hence making the pounding noise.
1) I changed the belt because the dryer is 10+ years old & it had many cracks.
2) I changed the belt tensioner.
3) I changed the LED light.