When you ship oversize freight, the length, height and/or width of the load dictate that you’ll need special permits for truck transportation. But often, of course, an oversize load is a heavy load as well. That’s why it’s important to understand the truck weight limits that apply to oversize shipments.

Whether a load fits in a standard, closed shipping container or it’s out of gauge cargo, the same rules about weight apply. A truck can travel on U.S. roads without special arrangements if its maximum gross weight comes to 80,000 lbs or less. When that truck drives onto the scale at a weigh station, its total weight—not just the freight, but the truck and all its equipment, the person in the driver’s seat, and the fuel in the tank—must come to no more than that amount.

Given the average weight of trucking equipment, you can usually transport about 44,000 lbs of freight in a 40-ft trailer or container without making special arrangements.

What if the load weighs more than 44,000 lbs?

Does that 44,000 lb maximum mean that when you want to move, say, two pieces of construction equipment in a container, and their total weight comes to 50,000 lbs, you have to ship two containers? Not at all!

By law, a specialized truck with the right heavyweight permit may carry 10,000 lbs more than a standard truck. That brings the maximum gross weight for an oversize shipment to about 90,000 lbs, making the maximum payload about 55,000 lbs.

We say “about” because actual limits vary by state. Local governments may set their own rules, too. So it’s important to work with a trucker that understands the rules and can get the right permits.

Weight, length and axles

Just as weight matters, so does the way you distribute that weight over the length of the chassis. The rules are based on a federal requirement called the Bridge Gross Weight Formula. While the details are complicated, the basic idea is simple: the heavier the oversize load, the longer the chassis you need to put it on, with the more axles underneath.

The reason for this rule is also simple. A 50,000 lb load on a 40-ft chassis exerts a lot more force per inch on a road or bridge than the same load spread along a 60-ft chassis. Weight distribution requirements keep heavy loads from wrecking the transportation infrastructure.

When a truck pulling an oversize load enters a state weigh station, an inspector there makes sure the dimensions and weight of the load match the figures on the permits, and also checks the weight distribution over the axles. Any infraction can bring a fine, a long delay, or both.

A lot of oversize freight—whether you’re shipping machines for factories, construction equipment or other massive objects—is shaped asymmetrically. It may be bigger at one end than at the other, or have parts that stick out. When you load one of those objects for transportation, it’s not always obvious how to distribute the weight. Stow planning software can help. But, in any case, you need to understand where the center of gravity is, and which parts of the load are heavier or lighter.  

Truck weight limits outside the U.S.

Oversize freight in Canada gets a bit of a break, as maximum weights there tend to be slightly higher than in the U.S.

But if you’re moving heavy freight in Canada, watch out for Spring Thaw policies. Each spring, as melting ice makes roads wetter and softer, some provinces temporarily reduce the maximum truck weights on their roads. The goal is to lower the risk of damage when road surfaces are most vulnerable.

The start and end dates for the Spring Thaw policy can change from year to year, and allowable maximum weights vary by province. So, if you’re shipping by truck within Canada, be sure to find out which regulations apply.

In Europe, the rules for truck weight are similar to the rules in the U.S. If your load can travel legally on the road in the U.S., you probably won’t have a problem overseas. Of course, details may vary by country. If you’re shipping to Europe, you need to understand the rules in your specific destination. And, of course, you’ll need to find a specialized carrier that can obtain the necessary permits.

Higher weight, lower cost

When you really understand truck weight limits, you may find that you can load more freight on a truck than you thought possible. And that, in turn, could reduce the number of containers it takes to ship your oversize freight overseas. Ocean carriers charge more to ship oversize cargo than they charge for standard containers, so the cost of shipping multiple oversize loads can really add up. By letting you ship fewer containers, a heavyweight strategy can save you a lot of money.

That’s why it pays to gain access to a network of specialized truckers that can provide the equipment and obtain the permits needed to transport heavyweight and oversize freight. To tap into this kind of money-saving network, contact the experts at I.C.E. Transport.