While the maximum gross vehicle weight for a commercial vehicle is 80,000 pounds, that does not mean your freight can weight 80,000 pounds. That total includes the combined weight of the semi-truck, trailer, and cargo.
A standard flatbed trailer can typically carry about 46,000-48,000 pounds of freight. However, that number alone does not determine whether a shipment can move legally.
For example, a 47,000-pound load may fit within a flatbed's typical freight capacity, but the answer can still depend on where the weight is concentrated, the trailer's axle configuration, and the states or provinces the shipment travels through.
In this article, you’ll find an in-depth overview of legal flatbed weights to help you make your next shipment a success.
Does It Matter How Weight on a Flatbed is Distributed?
Yes. Because the full 46,000-48,000 pounds of freight cannot rest on the trailer axles alone, the weight must be distributed across the tractor and trailer.
A typical flatbed tractor-trailer has five axles: one steer axle at the front of the tractor, two drive axles at the rear of the tractor, and two trailer axles under the trailer.
For a closed-tandem setup, the 80,000-pound gross vehicle weight is generally distributed as follows:
- Steer axle: 12,000 pounds
- Drive axles: 34,000 pounds total — 17,000 pounds per axle
- 2 Trailer axles: 34,000 pounds total
For a spread-axle setup, the distribution may instead be:
- Steer axle: 12,000 pounds
- Drive axles: 28,000 pounds total
- 2 Trailer axles: 40,000 pounds total
How Does Axle Configuration Affect Flatbed Weight?
How weight is distributed on a flatbed trailer depends in part on the trailer's axle configuration. Two common axle configurations are closed-tandem and spread-axle.
The right option for you will depend on your freight and route. The table below provides a quick overview of the key differences.
| Closed-Tandem Flatbed | Spread-Axle Flatbed | |
| Axle Configuration | Two axles grouped closely together | Two axles spaced farther apart |
| Typical Axle Spacing | 40-96 inches | About 10 feet |
| Freight Weight Limits for Trailer Axles | Up to 34,000 pounds | Up to 40,000 pounds |
| Best Suited For | Freight that can be evenly distributed across the trailer | Loads that need to meet specific axle or route regulations |
| Route Considerations | Can be used in all regions of the U.S. and Canada | Restricted in some states and provinces due to kingpin laws |
Closed-Tandem Flatbeds
What Is a Closed-Tandem Flatbed?
A closed-tandem flatbed is a flatbed trailer with a set of axles grouped between 40 and 96 inches apart. These are the most common types of flatbed trailers and are used to haul most open-deck cargoes, provided the commodity in question can be evenly distributed.
How Much Weight Can a Closed-Tandem Flatbed Carry?
Federal regulations limit the amount of weight a closed tandem flatbed (or any tandem grouping, for that matter) can carry to 34,000 pounds.
When Can You Use Closed-Tandem Flatbeds?
Closed-tandem flatbed trailers can be used in all regions of the U.S. and Canada. As long as your commodity can be distributed within applicable axle weight limits, they are not subject to the same kingpin-distance restrictions that can affect some spread-axle configurations.
Closed-tandem setups may also be preferred by some drivers because they can make turning easier and reduce wear on trailer components, including tires.
Spread-Axle Flatbeds
What is a Spread-Axle Flatbed?
Spread-axle flatbed trailers are trailers that have more distance between their two axles. Typically, spread axles are distanced 10 feet apart — a fair distance further than closed-tandem axle trailers which are usually spread no more than five feet apart.
How Much Weight Can a Spread-Axle Flatbed Haul?
This space between their axles allows spread-axle trailers to handle a bit more weight than their closed-tandem alternatives. Though your situation may vary — based on the make and model of your specific trailer — spread-axle flatbeds can hold up to 40,000 pounds of loaded freight weight on the trailer axle group.
When Can You Use Spread-Axle Flatbeds?
Unlike closed tandems, spread-axle trailers can’t be used in all situations. 53-foot spread-axle flatbed trailers, though capable of hauling concentrated weight up to 40,000 pounds on their axles, aren’t legally allowed in all states and providences in North America.
How do Kingpin Laws Affect Spread-Axle Flatbeds?
Kingpin laws regulate the allowable distance between a trailer's kingpin and the center of the rear axle group. Because the axles on a spread-axle flatbed are positioned father apart, some 53-foot spread axle configurations may not meet these requirements.
As a result, whether you can use a 53-foot spread axle flatbed may depend on the states or provinces your shipment travels through. In some locations, a closed-tandem configuration may be required instead.
California, for example, allows no more than 40 feet from the center of the kingpin to the center of the rear trailer axle — making closed axles the most common configuration for 53-foot flatbed cargo.
There are specialized 53-foot open-deck trailers with spread axles that may meet the kingpin distance requirement, but they are less commonly available.
Kingpin Distance Laws by State and Province
Kingpin laws vary across the U.S. and Canada. The map below shows kingpin distance requirements by state and province, including the maximum allowable distance for each jurisdiction.
What if Your Freight is Too Heavy for a Standard Flatbed?
Freight that exceeds the typical 46,000-48,000-pound capacity of a standard flatbed may still be able to move, but the shipment may require additional planning.
Depending on the total gross weight and route, an overweight permit may be required. Heavier freight may also require additional axles or a different trailer configuration to distribute the weight within legal limits.
To determine the right approach, your transportation provider will typically need details such as:
- Total freight weight
- Number of pieces and whether the freight is divisible
- Length, width and height
- Weight distribution and center of gravity
- Origin and destination
- Loading and unloading requirements
Frequently Asked Questions
Have more questions about flatbed weight limits? Here are answers to common questions about freight weight, axle configurations, and equipment selection.
Plan Your Next Flatbed Shipment With Confidence
Planning is key to successfully moving your freight. However, with regulations varying by state, province, and shipment type, it can be difficult to keep track of every requirement.
The specialized team at Anderson Trucking Service (ATS) has been moving open-deck loads for more than seven decades.
Not sure what trailer configuration or weight requirements apply to your shipment? Contact ATS to discuss your freight and get a quote for your next flatbed shipment.
Related Flatbed Shipping Resources
- Common Flatbed Trailers
- Federal Axle Weight Limits for Commercial Vehicles
- How Does Freight Weight Impact Trailer Type?
- Can I Overhang Freight on a Flatbed Trailer?
- What Can You Ship On a Flatbed Trailer?
- What is the Maximum Load Height on a Flatbed Trailer?
