What adjustment should be made last on a rack and pinion steering gear?

The adjustment that should be made last on a rack and pinion steering gear is the rack-to-pinion gear preload. This adjustment is critical because it ensures that the correct amount of pressure is applied between the rack and pinion gears to achieve optimal steering response and minimize play in the steering system. By adjusting this last, technicians can make sure that any previous adjustments regarding other elements, such as pinion bearing preload, spline preload, and rolling resistance, are properly set up. This sequence of adjustments ensures that the functionality and the feel of the steering system are both optimized, leading to smoother and more accurate steering performance. Additionally, making this adjustment last helps in achieving the necessary engagement between the gears without introducing excess friction or resistance that could affect steering feel.