Even the best cars develop problems as they rack up the miles. Parts wear, break down, and ultimately need replacement, following the natural order for cars. But components wear at different rates, as highlighted in the chart below.

Breaking out the data from our Annual Auto Survey reveals trends among the 17 potential trouble areas. We've sorted the average problem rates at three, six, and nine years to show the prevalence of some problems and how they increase over time.

Most categories cover multiple subsystems. For example, “Power Equipment,” the most frequently cited problem in 6- and 9-year-old cars, includes keyless entry, wiper motor and washer, tire pressure monitor, and the alarm and security system. In the chart below, the numbers 0 through 6 indicate the Problem Rate percentage.

See our complete guide to car reliability.

Car reliability trouble spots chart