Product review (5 stars): Fixed my issue of dryer getting stuck at 6 minutes
Apparently these little sensors need to be replaced periodically.  My dryer, when using sensor dry, would get stuck with 6 minutes left and then cook my laundry for about 2 hours.  These little pieces do the trick, but keep in mind you need 2 of them - you're simply buying the metal and not the assembly.

I went to YouTube for a video on how to replace mine, and it looked somewhat complex (i.e. taking apart the whole dryer).  What I found is that, if your head isn't ginormous, you can easily replace the pieces without totally disassembling everything.  You will need to unscrew the entire lint-catching grill assembly to get the pieces out (which isn't immediately obvious).  After that, replacement isn't too bad.  The whole process maybe took me 20 minutes.  Save yourself some money and do this repair on your own... it was fun!