Tread depth is below 2/32 of an inch
Tread wear bars are flush with the tread
Tires have cracks, cuts, or bulges
You see cords or fabric showing
The tire is losing air frequently
The vehicle vibrates unusually while driving
The car pulls to one side
Tires are more than 6 years old
Tires are more than 10 years old, even if tread looks okay
Uneven or excessive tread wear is present
You notice repeated punctures or sidewall damage
The tire has been repaired too many times
Wet traction has noticeably worsened
Snow or off-road traction has noticeably worsened
The tires no longer pass a safety inspection
The spare tire is being used because a main tire is unsafe