Reading the tread of your tires can foretell the future, sort of like reading your palm, or tarot cards. But it doesn’t cost you $1.95 a minute with Miss Cleo to figure out if your tires are good or bad.
Once a week, get in the habit of checking your tires for things like uneven wear and defects. Uneven tread wear can indicate suspension problems, poor tire maintenance or other impending hazards before they cause an accident or leave you stranded.
Here’s what you’re looking for in the tea leaves:
Wear in the center. Excessive wear in the center of the tread is most often due to overinflation. Check your tire pressure weekly, and look at the sticker inside the driver’s doorsill of your car for the recommended tire pressure. Never inflate your tires higher than the maximum rated pressure indicated on the sidewall. With overinflation, the edges aren’t contacting the road as much as they should, putting too much force on the middle section.
Wear at the edges. Underinflation is usually the cause of this type of wear, although wear at the outer edges can also be caused by aggressive driving. Underinflation causes too much force to be placed on the edges and not enough on the center.
Wear on one side. With this type of wear, the inside of the tread shows more wear than the outside, or vice versa. Poor alignment, worn ball joints, or other worn or bent suspension parts might be the cause. Bring your car in for a proper alignment and an inspection of your suspension components.
Feathering. Feathering means that each tread rib looks worn in one direction, such that one side is rounded while the other side is pointed, looking almost smeared outward. Sustained high-speed driving can sometimes cause feathering, although consistent feathering most often reveals an improper toe-in alignment setting. Again, take your car in and have the alignment checked by a specialist.
Cupping. Rounded, scalloped dips near one edge of the tread indicate severely worn suspension components. Go to your mechanic and have the suspension inspected immediately.
Flat-spotting. Flat-spotting, severe wear of the whole tread contact patch in one place on the tire, results from panic-braking (skidding) with the wheels locked up, usually on older cars without ABS. The flat spot will often introduce an imbalance that can be felt in the steering wheel. The imbalance from the flat spot makes the tires unsafe—replacement is the only safe solution, although if there is plenty of tread left on the tires, a professional tire shop might be able to shave the tread down.
Bald spots. Smooth spots on the tread, or areas between the edge and the center of the tread that are more worn than others, might indicate a wheel that’s way out of balance. Front wheels out of balance are usually easy to feel, but sometimes rear wheels are overlooked. Have your wheels balanced at any service station or tire store.
Swelling/bubbling. If you see any spots on the sidewall or tread that are visibly swelling outward or bubbling, go straight to your tire store and have the tire replaced. The tire might have been damaged by an especially deep pothole or piece of road debris. Change immediately to the spare if there are any doubts about the tire’s safety.
Some cars are actually designed to have slightly uneven contact patches and wear patterns, for better performance or roadholding. Check with your dealership if your tires are still wearing unevenly. Remember to monitor tread wear, and have your tires rotated when recommended by your owner’s manual for even, safe wear.