Diagnosis
That's a worn drum support roller. The rollers have a bearing that fails. The metal hub grinds against the roller frame.
How to Fix It
Unplug dryer. Remove the front panel and belt. Spin the drum by hand to locate the noisy roller. There are two at the rear. Replace both rollers (part # 310026) and the rear felt seal (part # 310378) while you're in there.
If That Didn't Work
A less common cause is the idler pulley bearing failing. It makes a high-pitched squeal or grind. Replace the idler pulley assembly (part # 310367).
Heads Up
Do not lubricate the rollers. It attracts lint and ruins the new bearings. Replace them.