After six years, the timer unit on my dryer became worn, which prevented it from turning. I also found all of the knobs developed slight cracks/fissures from wear and tear, so I purchased replacements for those. Using the video provided on the website, I was able to do the timer replacement myself. I had one slight variation from the video in the form of a hex screw that I needed to remove before getting the timer out (luckily I had the tool for that here), but otherwise, the rest of the steps were easy to follow. All told I saved $100 for a service call.