How should tires be inspected for tread depth?

Using a tread depth gauge or the penny test is the best method for inspecting tire tread depth because these methods provide a measurable and accurate assessment of the safety of the tires.

A tread depth gauge is a small, precise tool that can measure the exact depth of the tread grooves in millimeters or 32nds of an inch, allowing for a clear understanding of whether the tires are still within safe limits for traction and performance.

The penny test involves inserting a penny into the tread of the tire with Lincoln's head facing down. If part of Lincoln's head is visible, it indicates that the tread is worn down to a point where the tire may not perform safely, especially in wet conditions. This simple method offers a quick way to assess tire tread depth without specialized tools.

These approaches are standard practices in tire maintenance that align with safety recommendations, ensuring that drivers can maintain grip, effectively stop, and minimize the risk of hydroplaning in wet conditions.