Tire mounting... with but a few letters.

Jun 17, 2017

RAY: I'm going to have winter tires put on my car. I bought four of them. I'm moving soon, and since I'll be taking the car to a different shop to have them changed back next spring, the tires have to be marked so they can be put back where they belong, i.e., where they came from. So the left front has to go the left front, the right front has to go there, and so on.

When I take them off, I'm going to ask the people at the gas station to mark them with letters.

The question is, what's the smallest number of letters needed to mark my tires to guarantee that all four of them can get correctly installed with no chance of error or ambiguity in the spring?

Answer: 

RAY: The answer is two. Two letters and each is used twice. The two letters are L and F.

Here's how the tires would be marked. By the way, you could do this different ways, and you could use different letters, but this works.

The left front tire would be marked LF. The other front tire would simply be marked F.

The left rear tire would just be marked L.

TOM: And the fourth tire, which is the right rear, wouldn't be marked at all.

 


Get the Car Talk Newsletter