So the other day I went to turn on my heater and found that it was stuck in the feet position (not the ****). When I went to turn it to defrost it wouldn't switch. After about 4 mins it finally switched but it took a while. This just all of the sudden happened. I'm not quite sure where to start on this one. Wondering if anyone has had a similar issue?

 

blend door actuator

 

These trucks have a few of these blend door actuators. The common one has to do with temperature differences and is the one every one replaces.

There is also one for the selector which sounds like the one you are having an issue with.

However there is also one that works directly with the defroster as well. That might be causing you issues.

However before you order it you can take these out and see if you can move the flaps inside the HVAC system manually. Sometimes they get stuck, foam that seals it shut can fall off.