A vehicle is hard to steer. Which of the following is NOT a potential cause?

The correct answer identifies loose wheel bearings as not a potential cause of a vehicle being hard to steer. While loose wheel bearings can lead to other issues, such as excessive play and potential wheel wobble, they do not typically contribute directly to steering difficulty in the same way that other components might.

Seized kingpins and seized ball joints are both critical parts of the suspension and steering system that can directly impede steering by creating binding or lack of movement in the steering geometry. If either of these components is compromised, it can make turning the steering wheel feel much harder due to the increased resistance in the steering mechanism.

Excessive positive caster can also lead to steering difficulties. Caster angles influence the steering axis and the forces acting upon the steering system. When the caster angle is excessive, it can make the steering feel heavy and can affect the returnability of the steering wheel after a turn.

In summary, while loose wheel bearings can lead to problems with stability and alignment, they do not typically make steering more difficult. In contrast, seized components and improper caster angles can create direct steering challenges, making those the more likely causes of hard steering.