A few things could be going on here. If you are hearing metal on metal sound I would start with the blower wheel itself. Sounds like it either came loose from the motor shaft or it's broke. Other things could be a bad drum roller that has frozen up causing the rubber smell. Your idler pulley could be frozen up and the belt is slipping on the drum. Go to this link http://www3.sears.com/ and post your model number to get a breakdown of your dryer. It wil show the areas I mentioned. Catriver..post back.
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