With two balding tires, it's best to buy a new set

Dear Tom and Ray: Hey, guys! I need your help doing the unthinkable: proving my father wrong. I drive a 2003 Chevy Tahoe. I live in Atlanta and go to Georgia Tech, so most of my driving is city driving. With the constant stop and go, bumpy pavement and having to drive around people who are in the "big city" for the first time, my tires have worn out. The front tires are balding. Since the tires are bald up front, I was going to get them rotated, but even my rear tires don't pass the "penny" test, so I figured I should replace all of the tires. My dad says that at the most, I should replace only the front tires with brand-new ones. I explained to him that having tires with full tread in front and ones with little tread in the rear would be dangerous. He then said that I shouldn't replace my tires until the rear ones start to bald as well. By that time, my front ones will be racing slicks. How bad an idea is it just to swap the front tires with the rear ones? Or is the best solution mine: Just get all new tires?

Peri

Tom: Well, your solution is the right one, Peri. You need four new tires. But you need to have a little sympathy for the old man.

Ray: I trust he's still paying the bills these days. And I'm guessing that in addition to room, board, tuition, food, clothing, books, computers, ramen noodles and everything else the modern college student needs, he doesn't want to spend $600 on a set of tires right now.

Tom: But that's exactly what he has to do. If the front tires are bald, they need to be replaced. And if the rear tires have insufficient tread -- if you can see the wear bars, or they don't pass the penny test (insert a penny into the tread, Lincoln upside down, and if you can see the top of Abe's head, your tires are no good) -- then they need to be replaced, too.

Ray: You don't want to just swap the bad tires in the front with the slightly better ones in the rear. If you have one pair of tires that's better than the other, the good ones should always go on the back. I know that seems counterintuitive, but you never want to create a situation where the front of the car noses down during emergency braking and then the rear end of the car slides around or spins out.

Tom: So give Dad the bad news. But give it to him gently. Mix it in with some good news. Say, "Dad, I got an A on my physics test, I need $600 for new tires, and my girlfriend's not pregnant after all."

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