Here's the sector gear preload adjustment procedure I've used for a lot of years, and it seems to work well. Disconnect the Pitman arm, so only the steering gear is being turned, and use an inch-pound torque wrench on the steering wheel nut. With the steering gear turned off-center about one turn, check the turning effort. As the gear rolls across the center point, the turning torque should increase approximately 10 inch pounds, then drop to the previous reading once the center point is passed. For instance: Off centter, 10 in/lb, increasing to 20, then back to 10. Adjusting the sector gear preload bolt will change the center point preload if necessary. If the torque rises, then drops at the center point, rises again and then drops, the worm gear is worn out, and needs replacing.
Jerry
