I Just recently put my 4th reman steering box on the truck. With less then 200 miles on it I don't have power steering anything left of center. Is this an issue with the steering box or power steering pump. Going right its fine and there is no issue with the brakes.

 

Mine did that with the OE box at about 70k mi. Bad/stuck shuttle valve in the steering box.
Got a re-man form Napa on it now for the last 30k mi with good luck so far.
Why your 4th box? Lot of miles?

 

I am going to replace mine with a Borgeson when it gets replaced.. Seems like the right piece to replace a very old style of steering with a new updated model.
Not cheap but might be the last one you would need to put on.
http://www.borgeson.com/xcart/produc...productid=1685