I am trying to figure out if my auto locking hubs are stuck, can anyone advise me how to tell?

 

Jack it up and try turning the wheels. If the axle turns then they are locked. If I'm not mistaken which I may be these trucks use vacumn to hold the hubs unlocked and when the vacumn is gone then they lock. I'd this is the case you want to do this with the truck running.

 

On my old '94 150 I could tell they were still locked when I turned the steering wheel all the way and would feel the front wheels catching in the turn. Not sure if that would work too

 

read through this;

http://www.ford-trucks.com/forums/836438-everything-you-wanted-to-know-about-the-iwe-system-and-then-some.html