DEAR CAR TALK: Please settle this question for my daughter Abby and me.

Many years ago, I bought her a Toyota Solara for her high school graduation. It was only a couple of years old, with power everything. She loved it. (Dad wins points!)

All went well for a couple of years. Then, suddenly, she started hearing a “thunking” sound in the rear of the car. She took it to her mechanic, and the two of them went for a test drive.

They took a couple of corners, and the noise was quite apparent. He said, “I think you have a golf ball banging around in your trunk.” Sure enough, that’s what caused the noise.

My daughter was quite impressed that he identified it as a golf ball. I was not. (Dad loses all previously earned points.) My position is this:

Anyone can tell the difference between a golf-ball sound (compact and dense-sounding, with a slight “thwack” to it); and, say, a tennis ball (soft, with a slight fuzzy greenish timbre); a baseball (a good “crack” like a Ted Williams hit) or a football (which if in Tom Brady’s car, would make a slightly soft sound due to lower inflation).

I maintain that in order to call this mechanic a “genius” as my daughter wants me to, he not only would have to identify the noise as coming from a golf ball, he would have to identify the ball’s make and number (like Titleist No. 2).

Please give us the definitive answer so we can go back to talking to each other. – John

RAY: The guy’s pretty good, John. And even if he’s not a genius, he’s certainly watched a lot of reruns of “Columbo.”

Here’s what probably happened: He heard something rolling around in the trunk. He tested his theory by taking a couple of sharp corners and seeing where the noise came from after each turn. That allowed him to narrow it down, generically, to “ball.”

I mean, it could have been a can of Campbell’s chicken noodle soup, but a ball moves across the trunk more quickly and evenly than a soup can.

From its sound and timbre, as you say, he probably could tell it was small, and of medium weight. And then he made an educated guess.

What’s the most likely ball to be rolling around a car trunk? A golf ball that fell out of a golf bag, right? In fact, he’s probably had other customers who came in complaining about the same errant golf-ball problem.

So, even if he’s not a genius, he’s an astute observer. He’s also honest.

He could have said, “Oh, Abby, it sounds as if your struts and struts mounts are worn out. I’m going to have to keep it for a couple of days and it’s gonna cost you a thousand bucks.”

But he didn’t. So I’d call him an excellent mechanic, John. And I’d call him a good guy. And I would encourage Abby to call him whenever she has future car trouble.

Got a question about cars? Email Car Talk’s Ray Magliozzi by visiting the Car Talk website, www.cartalk.com.