Aug 22, 2022 3 min read

Weight Limits, OW Permits and Regulations

Trucks are subject to weight restrictions on roadways and must be appropriately weighted. The main reason for this is that the amount of damage to the road surface expressed for each addition ton per axle. The truck's ability to navigate and stop at highway speeds is affected by its weight. The government spends hundreds of billions of dollars every year maintaining and expanding roads, and weight limits are in place largely to prevent over-weight cars from causing harm to the national highway system. They aren't the same all around the country. If a truck can pass the Federal Bridge Formula test, it may travel up to 80,000 pounds on selected Federal routes. Many states don't need additional permits for larger weights.

Federal Bridge Formula:

W = 500(LN/N-1 + 12N + 36)

W = Overall gross weight on any group of 2 or more consecutive axles to the nearest 500 pounds.
L = Distance in feet between the extreme of any group of 2 or more consecutive axles.
N = Number of axles in the group under consideration.

Because the government spends so much money on creating and maintaining highways, it has imposed enormous overweight fines and penalties for anyone who breach the regulations they have established, whether voluntarily or unwillingly. This might result in penalties of up to tens of thousands of dollars, points on your driving record, the loss of your commercial driver's license, or even prison time. Each municipality has its own set of regulations that you must follow. That includes federal, state, and even local laws.

Trucks are built to handle specified loads, according to truck manufacturers. In most circumstances, the truck's structural integrity is built to handle at least the largest load that the maximum loaded axle weights for the routes to be traveled allow. Many trucks, in fact, are capable of hauling far larger loads than are legally authorized. As a result, some vehicles are built to transport the highest allowable weights in every situation, i.e., a truck may be rated for a maximum gross vehicle weight considerably in excess of 80,000 lb. In such situation, the vehicle's operator is responsible for being aware of the highway and non-highway restrictions for the route of travel, as well as not exceeding the specified legal or maximum permissible able gross vehicle or axle group weights for the routes on which the vehicle is to be driven.

Although the maximum permissible truck weight on Federal Highways is 80,000 pounds, the maximum allowed axle weights for single, tandem, and other axle combinations vary from state to state, often dramatically.

Tire width, number of tires, axle spacings, axle groups, and manufacturer's rating are the five factors used to compute overall restrictions (all of which vary by state). To establish your total limitations, the states will use the lower limit of all the factors.

"Seasonal weight restrictions" usually begin in early March and last until the middle of June. Because weather conditions vary from year to year, with temperatures ranging from below normal to above normal, most states and provinces reserve the right to adjust spring load restrictions based on observed seasonal rain and temperature conditions, weather forecasts, and soil moisture sampling to determine the dates for imposing and removing weight restrictions. States may purposefully be unclear regarding specific weight limits, preferring to make case-by-case choices and constraints. Contacting the state's highway agency may be the only method to get information.

Each state or province sets its own laws for heavy haul (maximum weights) transportation. The federal government does not issue licenses for large haul or overweight goods, nor does it control them. Each state is responsible for maintaining its own set of state rules. Overweight load permits are issued by the states. Bridge inspections may be necessary as part of these permits to verify that bridges are suitably rated for overweight loads.

Rates vary depending on the state and the amount of extra weight. Each state has its own set of restrictions and fees for heavy haul vehicles. Travel may be limited to specified days of the week and/or times of the day, depending on the actual weight of the cargoes, to avoid periods of normally high traffic. Travel periods for overweight vehicles are often less constrained; nonetheless, it is vital to examine state and municipal restrictions for the transportation of overweight goods.

Despite state disparities in the precise weight restrictions for different loads, one thing is ubiquitous: a permit is necessary to take the road in all 50 states. Even if your vehicle satisfies all legal criteria, you'll need a permit if the load is too big. Furthermore, you may be required to get a permit for each state through which your freight will pass.