The felt seals appear to have worn badly which caused a drag, which in turn caused the belt to slip on the motor pulley. Both the pulley and belt were ruined. Replaced the rollers at the same time, no brainer at the time. The seals, rollers, pulley, and belt were pretty simple to replace--actually very easy to repair. We have another dryer like it here and I will probably do the same to it before it has a problem.