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Home » How do I know when it is time to buy tires?

How do I know when it is time to buy tires?

Treat Test

Conduct this simple test to determine when it is time to buy tires.

Have you ever taken your car in for routine maintenance, only to get the bad news that your tires need to be replaced?   So has everyone else, and nobody likes this kind of surprise.  More so, nobody likes having to change a flat.

To help you avoid both, here are some very simple tests you can do at home. We recommend you do this each month to maintain safety.

  1. Place a penny in a tire’s shallowest tread groove with Lincoln’s head turned down.  If you cannot see the top of Lincoln’s head, you know you have more than 2/32” of tread depth remaining.  At this depth, your tires are acceptable for driving, but may start to get a little slippery in the rain. If you can see the top of Lincoln’s head, you have less than 2/32″ and should replace your tires right away.
  2. A second method, and our preference, is to place a quarter in the same area. If you cannot see the top of Washington’s head, you have 4/32” remaining.  At this depth, your tires are proven to be safer in rain.  At least 6/32” tread depth is recommended for safer driving in the snow.
  3. Wear bars are narrow bands of rubber that appear in the grooves across the tire tread. They are built into every tire and will show up when only 2/32″ of tire tread remains. If you can see the wear bars, you need new tires.

Tilly Mill Auto Center is a Family Owned and Operated, Full-Service Auto Repair Shop.

Convenient to Doraville, Dunwoody, Chamblee, Johns Creek, Norcross, Peachtree Corners and Brookhaven.

Hours and Payment

Payment Forms Accepted: Credit Card, Cash – No Personal Checks

Business Hours:

  • Weekdays: 7am – 6pm
  • Saturday: Closed
  • Sunday: Closed