Dryer stopped tumbling, ordered dryer repair kit and replaced belt, rollers and pulley. This was a great time to completely clean out 6 years of hidden lint (lengthy but not at all difficult process). Before reassembing we noticed that the motor pulley had broken and was probably the original culprit in the grand scheme of things. Ordered the part, watched the video and replaced before reassembling the dryer. In hindsight, it might have made more sense to just pull it all apart beforehand for more thoughtful ordering but in the end the dryer tumbles nicely.