noisy operation and then no heat

First I removed the two screws near the bottom of the front panel. Then I removed the front panel by rotating it outwards. Next I removed the front frame section by removing the four screws. The tumbler rests on this frame piece so remove it carefully and it will stay put - no need to take it out. The grinding noise I was hearing was the tumbler (drum) running on the frame - the glides (bearings) were worn out. This had generated piles of metal powder which I vaccumed up. It was easy to locate the reason there was no heat - the thermostat was burned to a crisp. It torched part of the blower seal in the process. The reason the thermostat fails in this manner is the lint duct gets clogged up increasing the duty cycle of the heater which fries the thermostat. I had to strip back the red wire and install a new blade connector but the thermostat just bolts on easy enough. You'll need a rivet gun to replace the glides. Drill out the old rivets and pull them out with some pliers. Easy enough to do and it runs like new! Good luck.