Steering Gear - Power: Description

Steering gear is a recirculating ball-type, available in either a constant or a variable ratio design. Steel balls form a "rolling thread" between steering gear worm shaft and rack/piston nut. Worm shaft thrust is absorbed by a thrust bearing and two races at lower end, and by a bearing in adjuster plug at upper end.

This design puts spring pressure on worm shaft to ensure proper thrust bearing preload. Adjuster plug provides initial preload adjustment and service adjustment (when repairing gear). As worm shaft is turned right, rack/piston is moved upward in gear.

As worm shaft is turned left, rack/piston is moved downward in gear. The rack/piston teeth mesh with sector, which is forged as part of sector shaft. Rotating worm shaft moves sector shaft, which turns wheels through mechanical linkage. See Figure .