When does a positive camber angle exist?

A positive camber angle exists when the top of the tire leans outward from the vehicle. This configuration generally indicates that the tire is angled away from the vehicle's centerline, which can influence handling characteristics and tire wear.

Positive camber can be beneficial in certain performance aspects, particularly during cornering, as it allows for better stability and contact patch management with the road surface. The outward lean can help in distributing forces more evenly across the tire surface when under lateral load, optimizing grip.

In contrast, the other options describe different conditions that are not related to positive camber. An inward lean of the tire would represent a negative camber angle, while the positioning of the ball joints and the condition of the rear axle are unrelated to the camber measurement of the tire itself.