Thinking it might be my steering box, but thought I would check here to see if there is a common leak in that area. The underside of the truck is newly wet with oil around the general area of the steering box.

 

I had a similar issue. While tearing everthing part for another repair noticed when I moved the ACE pump that the underside of the line coming out of the tank had burst, but I could not tell until I was moving the pump and flexed the line. It appears it is under no pressure so a large hole (probably almost an inch long) only leaked slightly until the hose was flexed. I do not know if it is a normal problem, but mine was one that could be easily missed had I not been working on something else.

 

mine had tiny leak at res to p/s pump hose. it was right at the reservoir and looked like it was coming from anywhere but there. I had to put that glow in the dark leak detection stuff in to find it

 

It's usually the power steering box, but could also be the line like dusty said.