Rotating your tires not only helps to distribute tire wear evenly but also it ensures that you'll get the maximum road life out of them, if your car is properly aligned you can see up to 25% more life from your tires. Refer to your owner's manual and it should give you a guideline on the rotation period and pattern. If not, a good rule of thumb is to rotate your tires every 6,000 to 7,500 miles.