My kit came in early this week.Rebuild kit from Amazon. Doesn't require replacing the entire actuator. 20 bucks versus 50+. Worth a look.
The culprit is a plastic gear grinding against a brass wormscrew gear. This one will probably outlast the rest of the service life of your Explorer.
I considered that, but came to the conclusion that it wouldn't have helped that much. The best part is, I have heat now! And a big thanks to everyone that contributed to this post, otherwise I never would have attempted it.Yeah, one of the hardest parts is figuring out the yoga poses you need to get into so you can reach the thing. I almost pulled the driver's seat out so I could lay on the floor.