The Penny Test, And Why It's The Bare Minimum

Hi, I'm James with Local Tire and Wheel. Been at this a little over twenty-five years now.

Today: "The Penny Test, And Why It's The Bare Minimum."

Let's get into it.

So the penny test works. I want to say that right up front — because I'm about to complain about it for four minutes.

It works. It just... only tells you one thing. And unfortunately it's the last thing you want to find out.

Here's the test, in case nobody ever showed you. Take a penny. Turn Lincoln upside down. Stick him headfirst down into the tread groove.

If the top of his head disappears, you've got more than two thirty-seconds of an inch of tread. If you can see his whole head... you're at it. Or below it.

Two thirty-seconds. Hang onto that number, because here comes the part nobody mentions.

Two thirty-seconds is the legal minimum in most states. That's the line where a tire stops being street legal.

It is not the line where a tire stops being safe.

Those are two very different lines. And there's a whole lot of road in between 'em.

See, on dry pavement — honestly? A worn tire stops about as well as a new one. And that's exactly why folks get comfortable.

But tread isn't there for dry pavement. Tread is there to move water. Those grooves are channels, and their entire job is getting water out from under that tire so the rubber can actually touch the road.

Shallower the groove, less water it moves. Simple as that.

So by the time you're down at two thirty-seconds, on a wet road, you've got very little margin left. Not zero. But... very little.

And you will not find out where that edge is until the one afternoon you really need to stop. And not much happens.

Okay, so here's a better test. Costs you twenty-four more cents.

Use a quarter. Washington's got a bigger head — if the top of it shows, you're down around four thirty-seconds.

And that's where I start telling people to make a plan. Not panic. Make a plan. Start watching prices, set a little aside, know what you're gonna do when the time comes.

Oh — and there's a free version built right into the tire, which I've always thought was a lovely piece of engineering.

Look down in the grooves. You'll see little raised bars running crossways. Those are wear bars.

When the tread wears down flush with 'em? You're at two thirty-seconds. The tire came from the factory with its own gauge built right in.

So go find a quarter. Check all four. And check a couple spots on each one — because a tire can look just fine on the outside and be bald on the inside.

That's a whole other conversation.

But if the quarter tells you you're getting close... don't wait around for the penny to tell you you're out of time.

The penny's the alarm. The quarter's the polite warning.

Alright. That's today.

Thanks for listening — and go check yours this week, would you? Costs you nothing. And if you don't like what the quarter tells you, come see us. Eight stores here in Arkansas, and we'll take a look for free either way.

We're local. It's in the name.

Talk to you soon.