Which alignment aspect is affected by a worn tie rod end on the left front of a vehicle?

A worn tie rod end on the left front of a vehicle directly affects front toe alignment. The tie rod ends are critical components in the steering mechanism, connecting the steering rack to the wheel assembly. If a tie rod end is worn, it can lead to excessive movement in the steering system, resulting in a misalignment of the wheels.

When the left tie rod end is worn, it can cause the left front wheel to not align correctly with the right front wheel, affecting how they point relative to each other. This misalignment primarily manifests as a change in the toe angle, which is the angle of the wheels when viewed from above—essentially whether the wheels point inward or outward. Proper toe alignment is essential for not only tire wear but also for vehicle handling.

Other alignment aspects, such as rear toe, front camber, and front caster, are not influenced by the condition of the tie rod ends as directly as toe. Rear toe pertains to the alignment of the rear wheels, while camber and caster are angles related to the tilt of the wheel and the steering axis, respectively. Thus, the correct choice is front toe, as it is the alignment aspect most affected by a worn tie rod end on the left front of a vehicle.