Problems experienced by operators of trucks powered by EPA-compliant diesel engines is “once again taking a toll on heavy-duty truck quality and customer satisfaction,” according to J.D. Power and Associates, which just released its 2012 “U.S. Heavy-Duty Truck Customer Satisfaction Study.”

The research firm said that overall customer satisfaction with heavy-duty trucks declined to 737 index points on a 1,000-point scale in 2012, compared with 751 in 2011, primarily due to an increase in the number of problems experienced.

Furthermore, the study finds that the quality of Class 8 trucks that are one model year old has decreased, with problem levels rising 9% to 223 problems per 100 trucks (PP100) in 2012-- up from 204 PP100 in 2011.

J.D. Power said that overall quality is determined by the level of problems experienced per 100 trucks, with a lower score reflecting higher quality and that “much of the overall quality decline is attributed to a higher rate of engine- and fuel-related problems, which have increased by 14% from 2011 (81 PP100 vs. 71 PP100, respectively).”

The firm noted that the “most problematic engine and fuel problems are driven by technology that is designed to reduce emissions from heavy-duty truck engines.”

“Following the revised EPA regulations in 2007, there was an increase in problems and a decline in customer satisfaction, and we anticipated the same thing would happen with the introduction of 2010 EPA-compliant engines,” said Brent Gruber, director of the commercial vehicle practice at J.D. Power and Associates. 

“Emission-related technology results in a high rate of problems, particularly with ECM calibration, exhaust gas recirculation (EGR) valves and engine sensors,” he continued. “The new, more complex engines are resulting in more problems and downtime.”

According to J.D. Power, vocational trucks are incurring an average of 2.2 unscheduled maintenance procedures per year, resulting in an average of 7 days of downtime, while on-highway trucks are suffering an average of 2.9 unscheduled maintenance procedures, for an average of 7.7 days of downtime.

“Engine reliability has the greatest impact on overall product satisfaction, so it’s vital that truck and engine manufacturers work quickly to reduce the number of problems related to the emission technologies,” said Gruber.

However, he also pointed out that “the truck brands of European companies have fewer problems, specifically, those related to the technology required to meet the emission standards, because they have been using the technology for years in other markets.”

Gruber explained that since 2008, Europe has had emission standards similar to those enacted in the U.S. market in 2010, so manufacturers that build heavy-duty trucks for that market have the advantage of applying technology proven in Europe in its U.S. models. 

The upshot, according to Gruber, is that “brands such as Freightliner and Volvo earn above-average satisfaction for engine reliability and dependability, as well as fewer engine- and fuel-related problems than industry average. On average, truck brands owned by U.S. companies experience 22% more engine- and fuel-related problems than their competitors owned by European companies (89 PP100 vs. 73 PP100, respectively).”

The study measured the satisfaction of primary maintainers of Class 8 heavy-duty trucks that are one model year old in two product segments: on highway and vocational. In each segment, satisfaction was determined by examining six key factors: cab/body; cost of operation; engine; ride/handling/braking; transmission; and warranty.

In the 2012 study, Freightliner ranked highest in heavy-duty truck customer satisfaction in both the on-highway and vocational segments.

In the on-highway segment, which evaluates both long- and short-haul trucks, Freightliner ranked highest with an index score of 750 and “performed particularly well in all six factors,” noted J.D. Power, while  Volvo ranked second (739) and Peterbilt came in third (736).

In the vocational segment, Freightliner ranked highest with an index score of 789 followed by   International (766) and Peterbilt (753).

The study also measured satisfaction with service provided by truck dealers via examining six factors: service advisor; service delivery; service facility; service initiation; service price; and service quality.

Kenworth ranked highest in Class 8 customer satisfaction with dealer service for a second consecutive year.  J.D. Power noted that Kenworth, with an index score of 804, “performs particularly well across all factors.” Following Kenworth in these rankings were Freightliner (802) and Volvo (784).

J.D. Power said the 2012 study was based on responses from 1,725 “primary maintainers” of one-model-year-old Class 8 heavy-duty trucks. The study was fielded in April and May 2012.