Westlake Village, California – While the initial quality of all-new or redesigned models improved every year from 2007 to 2010, the 2011 editions have declined considerably, according to the J.D. Power and Associates’ 2011 U.S. Initial Quality Study. The 2011 version marks the study’s 25th year.

The initial quality of vehicles overall has improved to an average of 107 problems per 100 vehicles (PP100) in 2011 from 109 PP100 in 2010, with a lower number indicating fewer problems. However, all-new or major redesign “launch models” worsened, from 111 PP100 in 2010 to 122 PP100 in 2011.

Carryover models, with no significant redesign in the past year, had better initial quality, at 103 PP100 in 2011 compared with 108 PP100 in 2010. The study measures owner satisfaction after 90 days of ownership.

“Exciting models with the latest features are crucial for winning over today’s demanding consumers,” said David Sargent, vice-president of global research. “However, automakers must not lose their focus on the importance of these models also achieving exceptional quality levels. Expected reliability continues to be the single most important reason why new-vehicle buyers choose one model over another, and no manufacturer can afford to give consumers any doubts regarding the quality of their latest products.”

The decline in vehicle launch quality was found primarily in the engine/transmission, and in audio/entertainment/navigation categories. The study suggested this was because automakers are designing engine and transmission software to make their models as economical as possible, but this sometimes leads to hesitation when accelerating or changing gears, a problem consumers are reporting more often this year than in past years. Automakers are also accelerating the introduction of multimedia technology, but some owners report that the systems are not intuitive or do not always function properly.

Among nameplates, Lexus led overall, with an average of 73 PP100, followed by Honda, Acura, Mercedes-Benz and Mazda. Land Rover posted the largest improvement in 2011, reducing its problems by 47 PP100 from 2010.

Honda took seven segment awards, for its Accord, Accord Crosstour, Element, Fit, Ridgeline, and in a tie in their respective segments, the Civic and Insight. Lexus received four awards for the ES, GS, GX and LS models, and for the second consecutive year, the Lexus LS had the fewest problems of any model, with just 54 PP100.

Chevrolet received awards for the HHR and Tahoe; Ford for the F-150 and Taurus; and Mercedes-Benz for the GLK-Class and E-Class. Other segment winners were the Cadillac Escalade, Chrysler Town & Country, Dodge Challenger and Mazda MX-5 Miata.

Among all-new or redesigned models, the Hyundai Equus and Dodge Durango each ranked second in their respective segments.

Three assembly plants, in a three-way tie, received Platinum Plant Quality Awards for producing models yielding the fewest defects and malfunctions: Toyota’s Cambridge South plant in Cambridge, Ontario (which produces the Lexus RX), Toyota’s Kyushu plant in Japan (Lexus ES, IS and RX) and Honda’s plant in Greensburg, Indiana (Civic). The plants average just 24 PP100. Plant awards are based solely on average levels of defects and malfunctions and do not include design-related problems.

In the Europe and Africa region, Daimler’s plants in Bremen, Germany (C-Class, E-Class and GLK-Class) and East London, South Africa (C-Class) tied and each received a Gold Plant Quality Award.

The study is based on responses from more than 73,000 purchasers and lessees of new 2011 model-year vehicles after 90 days of ownership.

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