Advanced or unusual tread wear can reduce the ability of tread to grip the road in adverse conditions. Check your tires for uneven wear, looking for high and low areas or unusually smooth areas. Also check for signs of damage.
When the tread is worn down to 1/16 of an inch, tires must be replaced. All tires have "wear bars," which are small, raised bars of rubber in the groove that indicate when tires are worn out. If your tread is worn down to the wear bars, it's time for a new tire.
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