Wear Indicators

The groove where the wear indicator is located is 1/16 inch (1.6 mm) shallower than elsewhere on the tire. If the tread has worn so low that the indicator is exposed, replace the tire. Worn out tires have poor traction on wet roads.
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Using tires that are excessively worn or improperly inflated can cause a crash in which you can be seriously hurt or killed. Follow all instructions in the owner’s manual regarding tire inflation and maintenance.