thumping sound in drum

My dryer makes a klunking sound every complete rotation. Its almost as if the drum is lifting and falling at the shaft. I can turn the drum by hand with ease and still hear the sound. Could this be the assembly-shaft (ball hitch) or the the rear drum bearing? thank you.

Front Felt Glide Assembly AP2150497 Upper dryer drum front felt seal with three glides sometimes wear out/off and causes the welded seal in the drumb to thump against the front assembly. Additional part to check is the rear drum bearing kit AP2142648.

Also check the drum seam.
Sometimes they can split.