When you go to a dealership to buy a new car, you get to take a test drive. But when you go to buy new tires, chances are you won’t be doing any testing before you buy them. Well this week our Over the Edge reporter Greg Carloss does the hard work for you.      

GREG CARLOSS: At MotorWeek when we test cars we’re evaluating the sum of a whole lot of parts. Well today I’m going to narrow my focus to the most important part of any car: the tires. As I spend a day in the life of a professional tire tester.

Buying tires online is fast and easy. But researching all the options is slow and stressful. Thankfully, tire testers can alleviate that stress.  

WOODY ROGERS: We test tires so consumers don’t have to. We want to share the information and let the consumer decide what’s most important to them and they can pick the right tire for their needs.

GREG CARLOSS: Given our shared interest in evaluating automotive products, we were invited to South Bend, Indiana, to review some ultra-high-performance all-season tires at a dedicated tire testing facility.

WOODY ROGERS: So, we know that not all tires perform the same, so we’re on a dedicated test track that demonstrates how tires will perform in an emergency avoidance maneuver-type situation. We also evaluate tires out on the road because their ride and their noise comfort and handling and steering feel are also not all the same. So, we evaluate all of those things on the road and out here on the test track.

GREG CARLOSS: For the most accurate results, variables must be limited. So, before they hit the test track, each tire being tested gets mounted on the same exact wheel, filled to the same exact PSI and installed on the same exact vehicle.

With that all squared away, we hit the road.

TJ CAMPBELL: For the road ride evaluation we’re really just kind of determining what a customer is going to experience or a driver is going to experience in their everyday life.

GREG CARLOSS: What are you feeling now and taking note of in this car?

TJ CAMPBELL: Well this portion of our route– it’s interesting that you’d ask right now. This is the absolute loudest section of road on our entire route, so I’m listening to the change in tone. I’m listening to the frequencies. Also I’ll do a little bit of just kind of, you know, very slight steering inputs for high speed responsiveness.

GREG CARLOSS: Once we get a feel for how the tires behave  on the street, it’s back to the track where we start with a braking test.

Now I feel like I’m at home.

After logging the stopping distance from 50 MPH for each tire, we head over to the skid pad to find the limits of lateral grip.

And I’ve already hit like three cones.

TJ CAMPBELL: You hit fewer than I did and I’m supposed to be the one who does this all the time. Alright you’re good.

GREG CARLOSS: Alright unloading.

Tire number one feels predictable with good grip, so let’s try tire number 2.

I feel like I’m having– I have less traction.

TJ CAMPBELL: You do. That is— that is an accurate assessment. You’re pushing wider.

GREG CARLOSS: Yeah, I keep pushing out I can’t stay in. And me being the aggressive driver, I refuse to slow down.

Wasting no time, we move onto the full circuit where we’ll combine braking and handling.

Again, it feels like tire number 1 out performs tire number 2. And when we stop to compare lap times, the numbers don’t lie.

TJ CAMPBELL: So you were, again, very, very consistent. I just want to get that on camera. Greg is an excellent tire tester.

GREG CARLOSS: Mom, I’m consistent!

TJ CAMPBELL: .14 seconds between your two laps, but your first tires were a 30.9 and a 31.0.

GREG CARLOSS: That’s a pretty big difference.

TJ CAMPBELL: Yes, yes. Almost 2 seconds in the dry around a tiny little 30-second track.

GREG CARLOSS: Wow. So now that we’ve done the dry, there’s only one option left.

TJ CAMPBELL: Turn on the sprinklers. Make it rain.

GREG CARLOSS: For tires, rain can be the great equalizer. And once the track is thoroughly soaked, we run all three tests again.

Unsurprisingly, the slick surface leads to longer braking distances.

Yep, never gonna stop.

TJ CAMPBELL: Nope.

GREG CARLOSS: Less lateral grip…

TJ CAMPBELL: You good?

GREG CARLOSS: And slower lap times…

That was miserable. But fun. But that time is not good.

With the actual testing done, their findings are published online including the objective performance numbers as well as the subjective impressions which they use to generate a numeric score. This allows customers to make a comprehensive and true apple to apples comparison for every tire tested.  

So, all in all, being a tire tester for a day turned out to be a lot of fun. And now when I’m testing cars, I think I’ll pay a little more attention to the rubber they ride on.