Sounds to me like the belt.
If the dryer makes noise, the belt may be frayed or damaged. If the belt is damaged, it will make noise every time it travels around the pulleys. The drive belt is a long, narrow band that wraps around the entire drum, then around a tension pulley and the motor pulley.
It is very common for dryer drum rollers to wear out. If the dryer makes noise, particularly a loud rumbling noise, one or more of the rollers may be worn out. After removing the drum from the dryer, inspect the rollers. If one is worn out replace all of them at the same time as a preventative measure.
Sorry mayer for messing with your answer. Just wanted to place the page from the manual to help out.
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Whirlpool 661570 Belt for Dryer
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