Have you tried adjusting it? Quick way to check if it's the box is have a friend lightly move the steering wheel back and forth through it's play area and see if the pitman arm moves at all. Note that he has to keep it in the play area without banging the edges of that area. If it doesn't move, then adjust the box a bit. Loosen the lock nut on top and turn the hex bolt counterclockwise while holding the lock nut. Do it in small adjustments (about a 1/4 turn) at a time and re-check the play. Do not make the steering to tight. You want to reach the first point of no play and leave it there. Now tighten the locknut. Make sure you can turn the wheel from lock to lock with no binding. If so, you're done. If not, back off on the adjustment some until there's absolutely no binding (you may have to live with a little play).