it is extremely unlikely that your machine is overheating. make sure your filter and condenser is clean(flush condenser with water to remove fluff).the temperature in a tumble dryer is regulated by the motor fan blowing air across the heater unit ,the thermostats are generally fail safe devices to prevent the heater getting too hot if the fan stops..
i suggest that you check the labels on your clothing ,make sure that they can be dried...most items will show some shrinkage in a dryer..
mike, September 2006