@drweldon sounds like a a faulty thermistor/thermostat. Of course, you also want to try to pull your dryer away from the wall, take off the exhaust vent hose, then run a load with the heated air just going into the room. If it drys good, then the issue is in your vent tubing in your house. You also want to make sure your motor is not clogged up with lint, causing it to overheat and shut down prematurely.
Item number 505 506 and 507 are the parts in question. While I am still trying to find the right tech sheet to assist you in the diagnostics, it might help if you post some of images of your dryen with the back cover removed. For that use this guide Adding images to an existing question