This weight limit applies to single trucks and tractor-trailers, and it is measured by the gross vehicle weight (GVW), which is the total weight of the truck, its cargo, and its passengers.
The GVW of a truck is calculated by adding the weight of the truck itself (known as the tare weight) to the weight of its cargo and passengers.
The tare weight of a truck can vary depending on the type of truck and its equipment, but it typically ranges from 15,000 to 25,000 pounds (6,804 to 11,340 kg).
The weight of a truck's cargo and passengers can also vary significantly, depending on the type of load being carried and the number of people in the truck.
However, for a typical tractor-trailer, the cargo and passengers can weigh anywhere from 25,000 to 55,000 pounds (11,340 to 24,948 kg).
Therefore, the GVW of a typical tractor-trailer can range from 40,000 to 80,000 pounds (18,144 to 36,287 kg).
The federal highway truck weight limit of 80,000 pounds (36,287 kg) was established in 1974 by the Federal Highway Administration (FHWA) as a way to protect bridges and roads from damage.
The FHWA also sets weight limits for other types of vehicles, such as buses and cars.
In addition to the federal weight limits, some states also have their own weight limits that are more restrictive than the federal limits.
For example, the state of California has a weight limit of 73,280 pounds (33,245 kg) for single trucks and 82,000 pounds (37,195 kg) for tractor-trailers.
