I thought it was the idler pulley, I used the videos to pull the dryer apart found that the blower wheel had been chewed up by a squirrel. As long as i was pulling the dryer apart decided to replace all rollers, new belt. Once i had the unit completely disassembled found and vacuumed everything found a dead squirrel in the vent. Reassembly went fairly quickly and dryer is working better than new. Just be aware blower is a left hand thread but the new one has markings to tell which way to tighten it on.