Because GM had the good sense not to hang the power steering pump right next to the exhuast manifold, although it is right on front of it, you can get by without replaceing the fluid for quite a while. I recommend to the service customers at my dealership that they service the fluid every 5 years or 60k. I recommend using pump of some kind to do it right. Justice Brothers Chemicals has a little pump that pumps out the dirty stuff, pumps clean stuff in. Then you just have to bleed the system by working the wheel back and forth, sucking out dirty fluid and adding clean as you go. That way you'll get the nasty stuff out of the lines and the rack. A turkey baster type set up or a large plastic syringe would work well.