A little over half of owners of one-year-old heavy-duty truck engines have experienced some type of problem in 2010
, according to the J.D. Power and Associates 2010 U.S. Heavy-Duty Truck Engine and Transmission Study released last week.

In contrast, prior to the changes in emissions standards implemented in 2004 and 2007, only 26 percent of owners of two-year-old truck engines experienced problems.

"Clearly, the emissions requirements have put a burden on engine manufacturers, and the result is that today's engines-although environmentally improved-are more problematic," said Todd Markusic, senior director of the commercial vehicle practice at J.D. Power and Associates. "Given the quality issues that arose from the last emission standards redesign in 2007, the new emissions standards in 2010 will no doubt create another challenge for engine manufacturers, but those that best handle the integration of these new standards will have a competitive advantage."

The study also finds that the number of engine problems increases by 55 percent, on average, after 50,000 miles of usage, up to 80.5 problems per 100 vehicles from 51.9 per 100 vehicles. As a result, satisfaction with engines decreases by nearly 40 points on a 1,000-point scale after 50,000 miles.

The J.D. Power study measures customer satisfaction with engines and transmissions in one-year-old heavy-duty trucks. Engines from Detroit Diesel and Navistar perform particularly well, the study found.

The most-commonly reported engine problems are issues with electronic control module calibration, cited by 14 percent of owners, and exhaust gas recirculation valve, at 13 percent.

The 2010 U.S. Heavy-Duty Truck Engine and Transmission Study is based on the responses of 1,682 primary maintainers of one model-year-old heavy-duty trucks. The study was fielded in February and March 2010.