I disassembled the dryer from the top down and removed the dryer drum. I inspected the 4 drum roller bearings and found a flat spot on one of the front drum rollers. I ordered and replaced both of the front drum rollers (replaced as a pair to ensure the same bearing diameters). This will help prevent a possible future drum failure due to excessive drum flexing. Believe it or not the hardest part of the repair was disconnecting the wires from the electronic control unit (fat fingers I guess).