Aug 30, 2021 · GVWR Range. Class 4 trucks. 14,001 to 16,000 pounds. Class 5 trucks. 16,001 to 19,500 pounds. Class 6 trucks. 19,501 to 26,000 pounds. Trucks in this category are different from refrigerated trailers because with reefer trucks the reefer unit is attached to the cargo box rather than a separate cargo hold.