The problem was a chunk had come off the drum drive belt. I ordered the part and it arrived in three days as promised. Replacing the belt was the easy part of the project. I hadn't been inside the dryer in years and it was full of lint and dirt. It took a lot more time to clean it than it did to replace the belt. While I had it opened I put a couple drops of oil on the drum support wheels. It should be good for another few years.