I have a 2004 F159 w 188,000 miles. The steering has become tight and will not return after turning. Power steering level is normal. Fluid smells fresh. Any ideas? Rack n pinion?

 

A good place to start would be to check ball joints and tie rod ends. I do not think that unit has rack and pinion steering . Correct me if I am wrong on that. You didn't state whether it was a 4X4, is it?

 

I believe that you have a rack and pinion assembly. I would look to see if you have any U-Joints on your steering shaft that connects to the rack. If any are exposed, the u-joints may be seized. Even if not exposed, they could be dry. I had that issue on my Freestar where it all of a sudden would not return to center and the steering was stiff. I sprayed the steering shaft u-joint (was exposed) with some WD-40 and it loosened right up like normal, but returned to stiff a couple of days latter. Replaced the steering shaft and all has been good for years.