How to Diagnose Tire Wear Patterns

Knowing how to read your tire wear is important.

Tires are an important part of your car's safety. Improper mounting, wrong size and improper inflation can all lead to poor car performance and driving issues. Another consideration is the tire wear pattern. The location of the wear and the pattern can give a clue to what is wearing down the tires.

Instructions

1. 

   Check your tire wear patterns.

   Examine your tire for wear patterns. Some of the most common tire wear patterns include over-inflation, which shows up as wear in the middle of the tread; under-inflation, which appears as wear on the sides of the tread; feathering, when each tread rib has a slightly rounded edge on one side and a rougher edge on the other; and cupping, which is when the tread dips dramatically around one edge of the tire or the other. See Resources below for images of these wear patterns.

2. 

   Worn tires can be dangerous.

   Determine how to correct the problem. Over-inflation can be corrected by letting some air out to meet tire pressure standards, while under-inflation requires adding more air. Feathering can be addressed by having a mechanic check the bushings in the front suspension, as they are probably worn. Cupping wear suggests that some part that connects the tire to the car is worn. These parts may include ball joints, wheel bearings, shock absorbers and springs.

3. 

   Use a penny to measure tire tread depth.

   Measure the tire depth. Tires are built with flat spots, called wear bars, in the tire groove that indicate tire wear. When the tread has worn down to the point that it is level with the wear bar, the tire needs to be replaced. Another option for measuring depth is the penny test. Place a penny upside down, with Lincoln's head toward the tire, in the tire groove or flat spot. If the top of Lincoln's head is showing, your tires need to be replaced, regardless of what wear pattern is on the tire. This means the tire tread is less than 2/32nd of an inch.

References

• AutoZone: How to Read Tire Wear Patterns
• AA1Car.com: Tire Wear
• Express Tire: How to Read Tire Wear

Resources

• AutoZone: How to Read Tire Wear Patterns