At what tread depth should tires be replaced?

Tires should generally be replaced when they reach a tread depth of 4/32nds of an inch. This is due to safety concerns related to traction and performance. At this level of tread depth, the tires have minimal capability to channel water away, increasing the risk of hydroplaning in wet conditions.

It is crucial to ensure that tires maintain adequate tread depth to provide grip, especially in adverse weather conditions. Regularly checking tread depth can help avoid issues related to handling, stopping distance, and overall vehicle safety. While some may consider replacing tires at deeper tread depths, 4/32nds is the commonly accepted threshold for safety and performance, especially within the rental car industry where the vehicle reliability and safety are paramount.