Tumble dryers do not have bearings. They have rollers that have inserts that wear out. You will have to remove the from from the dryer, pull the belt and the drum. You will then see the rollers that I am talking about. It is also possible that the idler shaft wore out and you will have to replace the shaft and the idler pulley. You didn't include what model or brand of dryer so it is hard to diagnose your troubles accurately.
Patrick
July 2010
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