When should you replace windshield wipers?

Answer: A — When they leave streaks on the glass.

Windshield wipers should be replaced when they leave streaks on the glass because this indicates that the rubber blades have degraded and are no longer making proper contact with the windshield. Streaks can significantly reduce visibility, especially during rain or adverse weather conditions, making it imperative for safety that the wipers are functioning effectively. While wipers can break, which would also necessitate a replacement, waiting for a break is less proactive compared to monitoring their performance and replacing them as soon as visibility is compromised. There isn't a strict timeline like every six months that applies to all vehicular conditions since usage and environmental factors can vary widely. Additionally, while preparing for winter is important, the specific condition of the wipers before adverse weather is the crucial factor that determines if they need replacing. Therefore, paying attention to the performance of wipers as indicated by streaking is the best practice.