To adjust steering knuckle vertical play, the technician would

• A. Tie rod ends
• B. King pin and bushings
• C. Wheel bearings
• D. Repack bearings

Answer: (B)

Vertical play in the steering knuckle comes from wear in the steering axis components, particularly the king pins and their bushings on many older suspensions. When these parts wear, the knuckle can move up and down relative to the axle, allowing unwanted vertical movement that makes steering feel loose. The fix is to inspect and replace worn king pins and bushings and, if needed, ream to the proper clearance so the steering axis is rigid again. After replacement, you would also verify alignment and torque specifications to ensure correct steering geometry. Tie rod ends control toe-in and the steering linkage, not the vertical movement of the knuckle, so they don’t address this issue. Wheel bearings primarily affect radial play at the wheel hub and can cause roughness or wobble, but they don’t restore the vertical rigidity of the steering axis. Repacking bearings handles lubrication, not correcting knuckle vertical play.