Introduction
A manufacturer needs to move a CNC machine from its plant to a new facility across the state. The shipping team requests a standard truckload quote, and the carrier comes back with a question: how much does it weigh?
The answer changes everything. At 92,000 pounds, that machine no longer qualifies for a regular flatbed or dry van move. It's now a heavy load, a specific legal classification that triggers state permits, specialized trailers, and often a police escort.
This scenario plays out daily across US manufacturing, construction, and energy sectors. Heavy loads aren't just "big shipments." They're defined by exact legal thresholds for weight and dimensions, and crossing those thresholds changes who can haul your freight and how.
This guide breaks down what qualifies as a heavy load, who's equipped to move one, and how heavy haul freight differs from a standard full truckload.
Key Takeaways
- A heavy load exceeds legal limits: 80,000 lbs, 8.6 ft wide, or 13.6 ft tall
- Moving one requires specialized trailers (lowboy, RGN, step deck) and state-issued permits
- Standard truckloads meet legal limits; heavy haul and superloads exceed them and need custom routing
- Working with an experienced, asset-backed carrier cuts down on delays, compliance risk, and permit headaches
What Are Heavy Loads?
A heavy load is cargo that exceeds standard legal limits for weight, width, height, or length. Once a shipment crosses those lines, it needs special permits, routing, and equipment to move legally on public roads.
The commonly cited thresholds that push a load into heavy haul territory include:
- Gross weight over 80,000 lbs on the Interstate System, the federal maximum under standard axle configurations (FHWA)
- Width over 102 inches (8.6 ft), the federal maximum on the National Network (FHWA)
- Height over roughly 13.6 to 14 ft, though there's no single federal height cap since each state sets its own limit
- Length beyond the 48-53 ft trailer range, depending on the state and trailer type
Exact numbers shift by state and by road system, so a load that's legal in Kansas might need a permit in Ohio.
Oversize, Overweight, or Superload?
These terms get used interchangeably, but they mean different things:
- Oversize refers strictly to dimensions, width, height, or length beyond legal limits
- Overweight refers to gross or axle weight beyond legal limits
- Superload is a catch-all for loads that exceed routine permit policy entirely, with no single national threshold across states.
Texas, for example, classifies certain nondivisible loads over 254,300 lbs as superheavy, while other states trigger superload review based on engineering factors like bridge stress.
Here's the part shippers often miss: a load doesn't need to look massive to qualify as "heavy." A compact steel coil or a dense piece of industrial equipment can weigh well past 80,000 lbs while sitting on a standard-sized trailer. Weight alone can trigger the classification, regardless of how the load looks.
Common Types of Heavy Load Cargo
Heavy loads show up across a wide range of industries, including:
- Industrial machinery and manufacturing equipment
- Construction and mining equipment (excavators, cranes, dozers)
- Prefabricated structures and modular buildings
- Energy and power equipment, such as transformers or turbine components
- Aerospace and defense components
Sims Global Solutions moves freight across several of these specialized sectors, including aerospace, defense, and material handling equipment.
Heavy Loads vs. Standard Freight
| Factor | Standard Freight | Heavy Load |
|---|---|---|
| Weight/dimensions | Within legal limits | Exceeds legal weight or size limits |
| Equipment | Standard dry van, flatbed | Lowboy, RGN, multi-axle trailers |
| Permits | None required | State oversize/overweight permits |
| Route planning | Standard routing | Bridge, clearance, and turn radius surveys |
Standard freight moves on routine equipment without special authorization. Heavy loads need all of the above before a truck ever leaves the yard.
Who Carries Heavy Loads?
Specialized heavy haul trucking companies, asset-based carriers, and freight brokers with vetted heavy haul networks haul heavy loads. Not every carrier can legally or practically handle this freight.
Equipment matters here. Heavy haul carriers typically run:
- Lowboy trailers for tall, heavy equipment that needs a low deck height
- RGN (removable gooseneck) trailers for drive-on loading of construction and mining machinery
- Step deck trailers for taller cargo that still needs road clearance
- Multi-axle trailers that spread weight across more axles to stay within legal per-axle limits
Moving that equipment safely also depends on the driver behind the wheel. A Class A CDL is required for most combinations, but drivers need more than a license.
Real experience coordinating pilot/escort vehicles and navigating each state's permit system matters just as much. About a dozen states require certified pilot/escort vehicle operators, and those certifications don't always transfer across state lines.
These permitting hurdles are one reason capacity access matters so much. Asset-based capacity is the differentiator. Sims Global Solutions carries heavy loads directly through its own trucking fleet, backed by the SimsTrak Transportation Management System. That combination gives shippers access to capacity that a traditional brokerage, which depends entirely on third-party carriers, often can't tap into on short notice.
Before booking any heavy haul move, shippers should vet:
- The carrier's permit-handling track record across multiple states
- Insurance coverage appropriate for high-value or oversized freight
- Direct experience moving similar cargo types
That vetting matters more than ever, since demand for this kind of specialized capacity isn't slowing down. Landstar, one of the largest heavy-haul carriers in the country, reported a 9% year-over-year increase in heavy-haul revenue in Q2 2025 and a 5% jump in revenue per load. That combination signals shippers are leaning harder on carriers who specialize in this freight.
How Are Heavy Loads Transported?
Moving a heavy load isn't as simple as hitching a trailer and driving. It follows a defined process, starting well before pickup day. Sims Global Solutions' heavy haul team manages each of these steps for shippers, from permitting through final delivery.
1. Permitting. The federal government doesn't issue oversize/overweight permits, states do. Each state along the route requires its own permit, submitted with load details, proposed routing, and axle configuration in advance.
2. Route planning. Before the truck moves, someone has to check:
- Bridge clearances and load capacity along the route
- Turning radius at tight intersections
- Road grades that could affect handling
- Local construction or seasonal restrictions
3. Safety and escort requirements. Depending on the load's size and the state's rules, carriers may need :
- Pilot or escort vehicles
- "Oversize load" banners
- Corner flags
- Amber warning lights visible from 500 feet
4. Scheduling. Permits often restrict travel to daylight hours, block weekend or holiday movement for larger loads, and pause entirely during bad weather. These windows can significantly affect delivery timelines, so they need to be built into the plan early.
Why Axle Weight Distribution Matters
Each of these steps hinges on one more factor: how weight gets distributed across the trailer's axles. Federal limits cap single axles at 20,000 lbs and tandem axles at 34,000 lbs, on top of the overall 80,000-lb gross limit, all governed by the Federal Bridge Formula (FHWA). A typical legal loading pattern spreads roughly 12,000 lbs on the steer axle and 34,000 lbs across each tandem group to stay compliant.
This is exactly why heavy loads need multi-axle trailers. Spreading weight across more axles keeps each one under its legal limit, even when the total load is well beyond standard capacity.
How Many Pounds Is a Full Truckload?
A standard full truckload (FTL) typically stays within the federal gross vehicle weight limit, commonly cited around 80,000 lbs on a standard 53-ft trailer. That figure covers the entire rig, tractor, trailer, and cargo combined, not just the freight itself.
Here's the key distinction:
| Shipment Type | Weight Status | Requirements |
|---|---|---|
| FTL shipments | Within routine legal limits | Standard equipment, no special permits |
| Heavy haul or superload shipments | Exceeds those same thresholds | Permits, specialized trailers, route planning |
For shippers, this is the practical line that matters. If your load's weight or dimensions push past standard FTL limits, even by a few thousand pounds, it shifts into heavy haul territory. That means a different type of carrier, a different quote process, and lead time for permits you wouldn't need otherwise.
Key Considerations Before Shipping a Heavy Load
Before requesting a quote, get your details right. A vague weight estimate or a missed dimension can delay permitting or, worse, get a shipment turned around mid-route.
Document everything up front:
- Exact weight, including any rigging or packaging added for transport
- Full dimensions: length, width, height
- Pickup and delivery site access, gate widths, ground clearance, turning room, and grade
Vet your carrier before booking:
- Confirm permit experience across the specific states on your route
- Verify insurance coverage matches your cargo's value
- Ask about past moves with similar equipment types
Plan early, especially for project deadlines. Permit approval, route surveys, and escort coordination all take time.
A shipment booked with only a few days' notice is far more likely to hit delays than one planned two to three weeks out. If your timeline is tight, say so upfront. Doing so changes how a carrier plans the route.
Frequently Asked Questions
What are heavy loads?
Heavy loads are freight shipments that exceed standard legal weight or dimension limits, commonly over 80,000 lbs, 8.5 ft wide, or 13.6 ft tall. They require special state permits and specialized trailers to move legally.
Who carries heavy loads?
Specialized heavy haul trucking companies, asset-based carriers, and experienced brokers with vetted carrier networks, like Sims Global Solutions, handle these shipments using lowboy, RGN, and multi-axle trailers.
How many lbs is a full truckload?
A standard FTL typically caps around 80,000 lbs gross weight on a standard 53-ft trailer. Anything heavier shifts into heavy haul classification and needs special permits.
What is the difference between a heavy load and an oversize load?
"Oversize" refers to a load exceeding dimension limits (width, height, length), while "heavy load" often relates specifically to weight. The two frequently overlap on the same shipment.
Do heavy loads always require special permits?
Most heavy loads need state-issued permits, since the federal government doesn't issue them directly. Requirements vary by weight, dimensions, and the specific route.
How much does it cost to ship a heavy load?
Cost depends on weight, dimensions, distance, required permits, and escort needs. Because every heavy haul shipment differs, it's best to request a tailored quote for accurate pricing.
