PORTLAND, OR – Daimler Trucks North America (DTNA) has made several executive appointments to support aftermarket and operations activities, with each effective on June 1.

Rich Simons becomes general manager – aftermarket parts sales, succeeding Jeff Wallis who retires after a 35-year career. Simons will be responsible for aftermarket sales, including parts and gliders.

He moves up from the role of general manager – central service, a post he has held since 2015. Previously he had served as president – Daimler Trucks Remarketing, director of used truck sales, and director of Freightliner and Thomas Built Buses parts sales.

Paul Romanaggi succeeds Simons as general manager – central service, where he will lead truck and powertrain service in the U.S. and Canada, including dealer and fleet field support, service engineering, call center support, new product service readiness, service literature and systems, and technical training.

He has held leadership roles in quality, warranty, parts pricing and sales, and service and parts distribution. In the last decade he has been general manager – supplier management and quality.

Carsten Kirchholtes becomes general manager – supplier management and launch change management, where he will be responsible for leading and driving targets and continuous improvement.

He joined Mercedes-Benz in Germany in 1992 and has been a director in German and U.S. purchasing departments.

Christoph Mertens succeeds Kirchholtes as general manager – procurement. He was most recently the head of Daimler Trucks Vehicle Modules and Platform Management in Stuttgart, Germany. Now he will oversee procurement in the NAFTA region and lead and drive global procurement activities in the cab commodity group.

Sungsoo Lee, currently the plant manager of Saltillo Truck Manufacturing in Mexico, becomes general manager – operations planning and quality management. In this role he will direct and lead customer application engineering, quality management, Six Sigma and production planning. Before serving as plant manager, he was the head of Mercedes-Benz and Chrysler passenger car production in China for the Beijing Benz Automotive Company. In 2000 he was general manager – manufacturing for Freightliner.