Appliance Parts Pros website provides various solutions to symptoms of failing appliance, located the specific symptom and likely parts required to repair my appliance. Completely disassembled dryer per instructions on Appliance Parts Pros website, very helpful. Cleaned with shop vacuum entire dryer, inspecting all components. Noted excessive belt dust near Idler Pulley Guide (not a wheel originally), and noted burn marks on guide from the drive belt. All components and wiring in good order. Reattached door switch and operated motor (without drum installed) to observe motor operating - no concerns. Contacted Appliance Parts Pros tech service for ohm specs on gas valve coils, and measured my gas valve coils with digital meter. Valve coils within specs as specified by Appliance tech at time of testing. Based on inspection decided to replace Idler Pulley with Wheel and Belt to eliminate squeak noise. Replaced Lint Screen Housing Foam on the Fan Chute (exhaust). Replaced Gas Valve Coils due to the age of appliance (20+ Yrs), most likely working intermittently, previously turning burner off during operation. Reassembled and tested appliance, and did not notice previously mentioned problems.
Over 2 weeks and gas dryer working perfect. Gas burner staying on the entire cycle. Squeak eliminated. Note: 2-day shipping is currently 1-week shipping due to excessive demands during COVID-19. Overall very impressed with Appliance Parts Pros service & parts availability & prices.