Gunnar has more than 40 years of experience in automotive manufacturing. He began his career at Saab Automotive AB in Sweden in 1981. He rose through the ranks working in roles including project engineer and executive director of labor relations. He also served as Executive Director Manufacturing for GM Poland. In 2015, he came to Volvo Aero AB, where he became Vice President and General Manager of Engine Products and then General Manager and Plant Manager of Volvo Trucks in Sweden.

In 2020, he came to the United States to lead Mack Trucks Lehigh Valley Operations, which is part of the Volvo Group North America and one of the Lehigh Valley's largest employers. He oversees the operations where all heavy-duty Mack trucks for the North American market are built. The Lehigh Valley assembly plant was recently expanded to support the production of electric heavy-duty trucks.

Gunnar and his wife, Paula, have two grown children. In his free time, he enjoys riding motorcycles, sailing, and golfing.