Have you ever wondered who is responsible for the size and weight limit of the thousands of trucks traveling the highways and interstates throughout the United States? The Federal Highway Administration (FHWA) Office of Freight Management and Operations is responsible for establishing and enforcing heavy truck size and weight standards on the interstate. Vehicle class and weight standards are illustrated in the chart below.
Total weight is a combination of the truck class weight, plus the load being hauled. Each individual state has established and set limits on vehicles that travel on their roads. In the state of Pennsylvania, The Pennsylvania Department of Transportation, (PennDOT) regulates the vehicles size and weight limitations. Each truck has their own gross weight rating set by the manufacturer. PennDOT sets the vehicles weight based on axle and wheel strength, horsepower, braking power, and other factors that could affect the vehicles ability to handle heavy loads.
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