KIRKLAND, Wash. -- Kenworth Truck Co. achieved the highest ranking in customer satisfaction among truck owners in the medium duty conventional truck segment and medium duty dealer service segment, according to the J.D. Power and Associates 2005 Medium-Duty Truck Customer Satisfaction Study(SM). The 2005 J.D. Power and Associates study is based on interviews with nearly 1,400 primary maintainers of medium-duty trucks (Class 5, 6 and 7). Customers gave Kenworth the highest scores in the industry in all six of the medium duty conventional product categories, including vehicle quality, cab interior, exterior design and styling, transmission, engine, and ride, handling and braking.Kenworth also received three awards from the J.D. Power and Associates 2005 Heavy-Duty Truck Customer Satisfaction Study(SM). In that study, Kenworth achieved the highest ranking in customer satisfaction among Class 8 truck owners in the over the road, pickup and delivery and dealer service segments. In addition, customers gave Kenworth the industry's highest scores in five of the seven service categories, including dealer attitude, service delivery process, price of service, service quality and service initiation.