I have some play in my steering wheel and want to try to adjust the slack out. I noticed an adjustment screw on top of the box. Can I safetly adjust the screw in a little to tighten it up? Does moving the adjustment screw change anything else? Any things to look out for, or tips that may be helpful?
I have never tried to adjust one of these boxes but i know the screw you are referring to is only for the "on center" feel. If you tighten it too much you'll have a hard spot
Are you sure the play is in the box? If so, yes you can adjust it out with the screw. It sets the pre load when in the center of the total lock-to-lock movement. Turing it in applies more preload. Go slow. Make sure you are checking your progress in the center.
Most steering boxes should only be adjusted with the pitman arm or tie ros disconnected. See a service manual for the correct procedure. A steering box should last the lifetime of a car/truck if kept properly adjusted and lubricated. If adjusted improperly wear will kill the box in short order.
Don't jump to open heart surgery for a little pain in the chest. Check out the play in the the tie rod ends, center link and idler arm first. I worked in a front end shop for over 20 years and I can't remember ever adjusting one of those boxes. I replaced a few that leaked but never an adjustment to cure slop. If you don't know how to check a front end just ask. It's not hard but it does take 2 people.