Alright, lately I've been noticing alot of movement in my steering wheel as i'm driving down the road. And I really noticed it as I was driving across a field behind my house, even abit of a banging noise as it moves left and right, almost as if the gears have alot of slop in them.

The truck is a 94 F150(305,000km), I replaced the balljoints and tie rod ends a month or two ago, so I know there is no slop, if any in those components. So I'm kind of assuming it must be my steering box. Have any of you replaced one before? And also, at 305,000km it should be an option right?