Owners of 3-year-old vehicles (2011 model-year) reported more problems than owners of 3-year-old vehicles last year, according to the J.D. Power 2014 U.S. Vehicle Dependability Study (VDS).

The study, now in its 25th year, examines problems experienced during the past 12 months by original owners of 2011 model-year vehicles. Overall dependability is determined by the number of problems experienced per 100 vehicles (PP100), with a lower score reflecting higher quality, according to J.D. Power.

The study finds that overall vehicle dependability averages 133 PP100, a 6% increase in problems from 126 PP100 in 2013. This marks the first time since the 1998 study that the average number of problems has increased.

“Until this year, we have seen a continual improvement in vehicle dependability,” said David Sargent, vice president of global automotive at J.D. Power. “However, some of the changes that automakers implemented for the 2011 model-year have led to a noticeable increase in problems reported.”

J.D. Power also found that the fewer problems owners experience with their vehicle, the greater their loyalty to the brand.

Combined data from previous years’ VDS results and vehicle trade-in data from the Power Information Network (PIN) from J.D. Power show that 56% of owners who reported no problems stayed with the same brand when they purchased their next new vehicle. Brand loyalty slipped to just 42% among owners who reported three or more problems.

“By combining our customer research with trade-in data, we see a very strong correlation between dependability and real-world brand loyalty,” said Sargent. “Also, we see that brands with lower dependability are likely to be shut out of a significant piece of the market, as many consumers will not even consider purchasing one of their vehicles because of concerns about its likely reliability.”

The Vehicle Dependability Study is used extensively by manufacturers and suppliers worldwide to help them design and build better vehicles, which typically translates into higher resale values and customer loyalty.

The 2014 Vehicle Dependability Study is based on responses from more than 41,000 original owners of 2011 model-year vehicles after three years of ownership. The study was fielded between October and December 2013.