eHow launches Android app: Get the best of eHow on the go.
Summary: The tire wear pattern will indicate if a car has an alignment problem. Interpret tire wear with the car maintenance tips in this free video on automotive repair from a professional auto mechanic.
"I'm Dave Erb from Dave's Ultimate Automotive and we'll be talking about how to interpret tire wear. When looking at a tire there's several kind of wears you'll come across. Some of them are alignment wear and this is going to be where the inside or the outside of the tire is going to be shaved down or worn much more so than the rest of the tire, that's going to be an alignment issue. Other things you'll come across is if you see wear on both outer edges and the middle looks good, that's going to be an under-inflated tire because the inside will dip down and it will ride on the outer edges. An over-inflated tire will wear in the center because the over inflation is pushing the center out, so you'll have good tread on the outside and you'll see much more wear in the center of the tire. The other most common problem or tire wear indicator is what they call "cupping" or "scalloping". And what that is it looks like the tread of the tire is almost like a mountain range, it will have a lot of up and down and uneven treads from one tread to the next, and that's usually caused by either a balance issue, a lack of balance, out of balance, or it will be caused by a worn part, bad shocks, worn out suspension parts. You usually see scalloping or cupping problems on the front, although they can happen on the back, and once again that indicates either a balance issue, shocks or worn parts. So just by looking at a tire and seeing how it's wearing you can tell whether it's an inflation issue, an alignment issue, or a part's wear issue. So that's how you interpret tire wear."
eHow Article: How to Interpret Tire Wear