The Two-Minute Tire Check: Tread Depth and Pressure

By the Genesis Driving Academy Team · September 14, 2026

Key Takeaways

Your tires are the only part of the car touching the road, and most tire problems are visible long before they cause trouble.

• Check pressure once a month, when the tires are cold.
• Use the pressure on the sticker inside the driver's door, not the number on the tire.
• The penny test shows when tread is getting too thin.
• Worn tread matters most in the rain, when it cannot clear water.
• Look for bulges, cracks, and uneven wear while you are down there.

Why this matters more than it seems

Tires wear slowly, so the change is easy to miss. A car with worn tires will still feel normal on a dry, sunny day.

The difference shows up when you need it. Tread grooves channel water out from under the tire. As they get shallower, the tire has less ability to push that water aside, and it can ride up on a film of water. That is hydroplaning, and it can happen at ordinary highway speeds on worn tires.

Low pressure causes its own problems: longer stopping distances, weaker handling in a sudden swerve, extra heat, and faster wear on the edges of the tread.

Step 1: Check the pressure

Find the right number. Open the driver's door and look for a sticker on the door jamb. It lists the recommended pressure for your car, sometimes different for front and rear tires. The number molded into the tire sidewall is the tire's maximum, not what you should fill it to.

Check when the tires are cold. Driving heats the air inside and raises the reading. Check first thing in the morning or after the car has been parked for a few hours.

Use a gauge. An inexpensive pen-style or digital gauge works fine. Remove the valve cap, press the gauge on firmly, and read it.

Adjust. Add air until you reach the door-sticker number. If you overshoot, press the small pin in the valve to let some out, then recheck.

Do not forget the spare, if your car has one. A flat spare is no help on the side of the road.

A note on the dashboard warning light: many cars have a tire pressure monitor, but it typically only warns when a tire is already significantly low. A monthly check catches problems earlier.

Step 2: Check the tread with a penny

1. Take a penny and turn it so Lincoln's head is upside down.
2. Insert it into a tread groove.
3. If you can see the top of Lincoln's head, the tread is worn thin and it is time to shop for tires.

Check several spots across each tire: the inside edge, the center, and the outside edge. Tires rarely wear perfectly evenly.

Many tires also have tread wear indicator bars, small raised bridges running across the bottom of the grooves. When the tread wears down level with those bars, the tire is worn out.

If you drive often in rain, consider replacing tires before they reach the penny-test limit. The loss of wet grip starts well before the tread is fully worn.

Step 3: Look for warning signs

While you are checking, take a quick look around each tire for:

• Bulges or bubbles on the sidewall. These signal internal damage and can lead to a blowout. Get it inspected right away.
• Cracks in the rubber, common on older tires or cars that sit a lot.
• Nails or screws in the tread.
• Uneven wear. Wear on both edges usually means low pressure. Wear in the center can mean overinflation. Wear on one edge often points to an alignment problem.

Make it a habit

Tie the check to something you already do each month, like the first fill-up of the month. It takes about two minutes, costs nothing, and it is one of the few safety checks that gives a clear answer right away.

Good tires will not make up for following too closely or driving too fast for the weather. But worn or underinflated tires can quietly take away the margin you were counting on.