Lowboy trailers are an essential piece of equipment in the transportation and logistics industries, specifically designed to haul heavy, oversized machinery and loads that exceed the height limits of standard flatbed trailers. One of the most important specifications to understand when dealing with lowboy trailers is their width, as it determines the type of cargo they can legally and safely carry. The width of a lowboy trailer not only affects transport planning but also influences whether permits or escort vehicles are required. Knowing how wide a lowboy trailer is and how wide it can legally be is crucial for anyone involved in shipping, freight logistics, or heavy equipment transport.
Standard Width of a Lowboy Trailer
Typical Dimensions
The standard width of a lowboy trailer in the United States is8 feet 6 inches(102 inches), which aligns with federal highway regulations for most commercial vehicles. This width allows the trailer to travel on most highways without needing an oversize permit. In metric terms, this is approximately2.6 meters.
Why 8’6′ Is the Standard
This width is not unique to lowboy trailers it’s standard for many types of trailers including flatbeds, dry vans, and refrigerated units. The 8’6′ width is considered the legal limit for vehicles traveling on highways without additional permits, which makes it the default specification for most manufacturers building lowboy trailers for general use.
Extended and Oversized Widths
Wider Lowboy Trailers
While the standard width is 8’6′, many lowboy trailers can be customized or equipped with features likedetachable side extensionsoroutriggersto support wider loads. These extended trailers are used for hauling items like construction machinery, cranes, or military equipment that exceed the base trailer’s width.
Permit Requirements for Wide Loads
When a load or trailer exceeds the 8’6′ limit, it is classified as awide load. This classification comes with regulations, such as:
- State-issued oversize permits
- Escort or pilot vehicles for certain routes
- Limited travel hours (no night or holiday travel in many cases)
- Use of signage and flashing lights
In some states, trailers up to 10 feet wide may be permitted with fewer restrictions, but anything over that typically requires careful planning and coordination with transport authorities.
Lowboy Trailer Width and Cargo Compatibility
Understanding Cargo Width
When loading a lowboy trailer, it’s important to consider both the width of the trailer and the cargo. If the cargo width exceeds the trailer’s width, you may need to use outriggers or specialized extensions to support the load.
Common Wide Load Cargo Types
- Bulldozers
- Excavators
- Transformers
- Wind turbine components
- Bridge beams
These types of machinery often surpass standard trailer widths, making lowboy trailers with adjustable width features essential.
Legal Regulations by Region
United States Regulations
The Federal Motor Carrier Safety Administration (FMCSA) sets the nationwide legal width limit at 8 feet 6 inches. However, local and state regulations can vary, particularly in urban areas where narrow streets or low bridges are a concern. States like California, Texas, and Florida may have additional rules depending on the load type and the roads being used.
International Standards
In Europe and other parts of the world, the standard width of trailers may vary slightly. In many European countries, for example, the maximum legal width for trailers is typically2.55 meters(about 8 feet 4 inches), which is slightly narrower than the U.S. standard. If you’re transporting cargo across borders, it’s vital to know these regional differences.
Design Features Affecting Width
Outriggers
Outriggers are fold-out or removable supports that allow you to increase the usable width of a lowboy trailer to accommodate broader loads. When not in use, these supports can often be folded in or removed entirely to return the trailer to standard width.
Detachable Goosenecks
Some lowboy trailers have detachable goosenecks which make it easier to load and unload heavy equipment by driving it directly onto the trailer. While not directly related to width, these features often complement wide cargo needs by offering better clearance and entry points.
Considerations When Choosing a Trailer Width
Type of Cargo
Before selecting a trailer, know the exact dimensions of your load. If your machinery or cargo exceeds the standard width, you’ll need either a wider trailer or to transport the load under a wide-load permit.
Route Planning
Certain routes may not accommodate wide loads due to bridge widths, road lanes, or local laws. It’s important to plan a route that allows for the full width of both the trailer and cargo, especially if you’re moving through multiple states or countries.
Cost and Logistics
Wider trailers and the permits associated with wide loads can significantly increase transportation costs. If possible, consider whether disassembling your load or using a different method of transport could be more economical.
Benefits of Standard-Width Lowboy Trailers
- Ease of mobility: Fits within legal highway limits, reducing restrictions.
- No permit needed: Saves time and money on paperwork and escort vehicles.
- Faster loading and unloading: Compatible with most docks and equipment ramps.
- Greater availability: Standard-width lowboys are more widely available from rental and freight companies.
When to Use a Wider Trailer
Wider lowboy trailers are essential when your equipment simply cannot be broken down into smaller dimensions or when transporting pre-assembled components. This is especially true in industries like:
- Construction
- Agriculture
- Mining
- Energy (wind, solar, and gas sectors)
These trailers offer flexibility, but they also demand more preparation, permitting, and operational caution.
The width of a lowboy trailer is typically 8 feet 6 inches, aligning with U.S. legal highway regulations. However, for cargo that exceeds this width, lowboy trailers can be customized or equipped with extensions to support wider loads. Knowing how wide a lowboy trailer is and what that means for legal transport, permitting, and load capacity is crucial for safely and effectively transporting oversized equipment. Whether you’re hauling heavy construction machinery or coordinating a multi-state freight operation, understanding trailer width helps you make better logistical, financial, and legal decisions.