Whirlpool Gas Dryer Has the Squeaks

Google search will probably lead you to a top 5 list of causes. then on to Youtube 'how to" videos. In my experience a constant high pitch almost whistling squeak is either the little plastic roller of belt tensioner or the bearing at center of rear drum. Not all brands/models have that bearing at rear center of drum. If its the tension idler, consider a new belt. Every part except the timer is reasonably priced.