Hello, my husband and I are trying to repair our frigidaire dryer that is less than 15 months old. It began when the dryer stopped heating so we took it apart and changed the heating element coil. After putting it back together, it ran fine for 2 minutes or so, heated, did everything correctly, but then began making a thumping noise. We then took it back apart and have found that the sound is coming from the center back of the machine. We are assuming that it may be something in the drum support. How should we make sure to diagnose the problem correctly and get the correct part? Why would this all of a sudden begin after changing the coil? My husband did actually put the belt back on with the ridge part up which from what I have read is incorrect. Could that have caused this to happen?