Heavy-duty truck engine quality has improved from 2010, after technology changes related to emissions standards revisions caused a spike in engine-related problems during recent years, according to the J.D. Power and Associates 2011 U.S. Heavy-Duty Truck Engine and Transmission Study released Sept. 1.
The 2011 study finds that 42 percent of owners of heavy-duty truck engines that are one model-year old report experiencing some type of engine-related problem, down from 46 percent last year. However, this is still well above the historically low average in 2004, when 26 percent of owners of truck engines that were two model-years old reported experiencing a problem. This low problem incidence level occurred prior to implementation of two rounds of emissions standards revisions in 2007 and 2010.
The most-commonly reported engine problems are issues with the exhaust gas recirculation valve (cited by 23 percent of owners) and electronic control module calibration (21 percent).
Also in 2011, engine problems have decreased to an average of 66 problems per 100 vehicles (PP100) from 72 PP100 in 2010. As a result, satisfaction with engines has increased by 22 points to an average of 739 (on a 1,000-point scale).
Navistar’s International MaxxForce engines rank highest in customer satisfaction with a score of 760 and perform particularly well in four of eight factors: engine reliability and dependability, engine warranty, vibration at idle and average fuel economy.
The study measures satisfaction among primary maintainers with engines and transmissions in Class 8 trucks that are one model-year old. Satisfaction is measured based on eight key factors: engine reliability and dependability; engine warranty; acceleration when fully loaded; electronic control module; accessibility to components for service or maintenance; vibration at idle; maintaining speeds on grades; and average fuel economy.
Overall satisfaction with heavy-duty truck transmissions averages 820 in 2011, up two points from 2010. Although transmissions are typically not problematic during the first year of ownership, satisfaction among owners who experience at least one transmission-related problem averages 123 index points lower than among owners who did not experience problems (829 vs. 706).
The study is based on the responses of 1,651 primary maintainers of Class 8 trucks that are one model-year-old.
