25 problems have been reported for the 2009 Cadillac STS. The following chart shows the 12 most common problems for 2009 Cadillac STS. The number one most common problem is related to the vehicle's air bags with 5 problems. The second most common problem is related to the vehicle's electronic stability control (5 problems).
In our research we use the PPMY index to compare the reliability of vehicles. The PPMY index of a certain model is defined as the problems reported per thousand vehicles per Year. The total sales of the 2009 Cadillac STS in the United States are 7,239 units . If the total number of problems reported by Cadillac STS owners in the last 10 years is 25, and the age of the vehicle is 10, the PPMY index can then be calculated as
PPMY Index = 25 / 7,239 / 10 * 1000 = 0.35.
For more information, refer to this page: A study of reliability comparison across Cadillac STS model year vehicles.
The following chart shows the number of problems reported during each of the service years since the debut of the 2009 Cadillac STS in 2009.
|Service Year||Number of Problems|
When making the decision between buying a new or used Cadillac STS, the following table can be used to compare the 2009 Cadillac STS with the Cadillac STS from other model years. Note that the number of problems reported for the 2009 STS is 25 while the average number of problems reported for the 14 model years of the Cadillac STS is 38.