Originally Posted by bmcd308

I have tried to buy used tires from sellers on this (and other) car boards before. The ads all say that the seller just wants a reasonable price, which is probably true. I make what I believe to be a reasonable offer, and they think (or even tell me) I’m a jerk.

What happened?

Well, let’s talk about what the seller is selling. A new set of tires has 10/32 of an inch of tread on it, and you paid, for purposes of this example, $1,100 for the tires + $100 to the tire shop guy = $1,200 mounted and balanced for them. Later, you got some different tires, so you loaded these in your wife’s SUV and brought them home to try to recoup a few bucks.

Now, let’s just say for a moment that you are one of the very few people who actually measures the tread depth. You measure 5/32. New was 10/32, so you say these have “half their tread left” in your ad. Then, you say to yourself, “Self, you paid $1,200 for these. They are half used. $600 is fair.”

What is the problem with this logic?

Well, first, you did not use half the tread. Tires are not legal in most states with less than 2/32 of tread left, and many (myself included) consider tires fully worn out for street purposes (where they might be driven in the rain) at 3/32. That means that only 7/32 of USABLE tread was on the tires when you bought them. You used 5 of those 7. So you did not use half the tread; you used 5/7 of the tread. I am only buying the last 2/7.

Let’s say you are convinced so far. So you say to yourself, “Self, this sucks. We only have 2 of our 7 usable units of tread depth left to sell. 2/7 of $1200 is $343. We are going to have to take $343 for these things, not $600.”

The world is hard, and it’s even harder than you see described here.

If I bought a new tire, I would get all 7/32 of USABLE tread life, mounted and balanced, for $1,200. That means for each of my 7 units (1/32 of an inch), I would pay $171. Now, I’m only buying 2 units of tread life, so you might expect me to offer $340. The problem with that is that I have to get them mounted and balanced, and I have to pay the whole $100. The tire guy is mounting four whole tires, not 2/32 of four whole tires.

For me to get 2/32 of tread life for $340, I can only pay you $240, because the mount and balance guy gets his $100.

So the preliminary price for your tires is not $600, but $240, and that is before we talk about the fact that your tires are not new and therefore have no mileage warranty, that if I bought new I might get free road hazard thrown in, that it is less convenient to buy tires with 2/32 of tread than with 7/32 of tread, etc.

So anyway, the next time you get an offer for $150 to $200 for your tires that you “estimate” to have 50% of their tread life, don’t tell yourself the buyer is trying to screw you. Say to yourself, “Self, a worn out set of tires just really isn’t worth anything.”