Where should you measure tire tread depth?

You should measure tire tread depth in several locations across the tire to get an accurate assessment of wear. The best places are the grooves in the tire tread, specifically in the center, on the inside, and on the outside edges. Use a tread depth gauge or a penny to check; placing the penny with Lincoln's head down into the groove will help you determine if the tread is deep enough. Generally, a tread depth of 2/32 of an inch or less indicates that the tire needs to be replaced.