Home 2019 Chevy Silverado Medium Duty: Why the Low Weight Rating? (Ask TFLtruck) Chevrolet unveils the 2019 Silverado 4500HD, 5500HD and 6500HD at NTEA The Work Truck Show, March 7, 2018. GM Fleet’s Ed Peper, U.S. vice president, and John Schwegman, director of Commercial Product and Medium Duty, present the trucks to customers, upfitters, dealers and media.