I took the tumbler drum out and looked at the pulley and it was not rotating freely. The idler arm had some wear on the attached post so I replaced bothe parts. Since I was in there already I replaced the drum rollers and dryer belt for good measure. I reassembled the dryer and it works great.
The best part of the experience was the parts order. I ordered the parts around 3:00 pm one day, standard shipping, and they were on my doorstep around 1:00 pm the next day. I'm still wondering how AppliancePartsPros managed such extrordinary customer service. Hat's off to them!