As your clothes dryer gets older, it can start to leave marks on your clothes. There is a cloth bearing in the back of the dryer drum that collects small amounts of lint and it burns in the heat of the dryer and added friction of the rotating drum. The result is a brown dust that unfortunately stains whites badly. This video shows how to quickly fix your dryer.
Step 1 - Take dryer drum out
Step 2 - Clean cloth bearing with 409 and rinse
Step 3 - Put dryer drum back in