How to Gauge the Tread on Tires

The depth of tread on a tire is one of the most important aspects of a tire's performance. The tread is used to help the tire grip the road and prevent accidents. Also, the depth of the tread is an indicator of how much life is left in a tire. Lower tread depth means less life and an increased chance of tire malfunction. Tire tread gauges can be purchased online or at any automotive store, but with just some loose change tread depth can be approximated in a few seconds.

• 1

  Park the vehicle on a flat, level surface and set the parking brake.

• 2

  Place a penny in the tread of the tire with Lincoln's head pointed at the tire. If any part of Lincoln's head is covered, the tread is more than 2/16 inch deep. Measure different areas of the tire, starting at the center and working towards the outside of the tire. The overall tread depth will be the average of the individual depths.

• 3

  Repeat the process with a quarter, aligned with Washington's head pointed at the tire. If any part of Washington's head is covered, the depth of the tread is at least 4/32 inch.

• 4

  Repeat the process a third time with the penny again, but this time align the penny so that the top of the Lincoln Memorial is pointed at the tire. If the top of the Lincoln Memorial is covered, the tread is at least 6/32 inch.