Types of truck trailers: what each one hauls and how big it is

A truck trailer is only as useful as the freight it can legally carry. Pick the wrong type and you either can't take the load or you haul air. This guide covers the main types of truck trailers on US roads, what each one hauls, typical sizes and the legal limits that shape them, from the point of view of the carrier who has to keep them loaded.

Dry van

53 ft · 101 in wide inside · ~110 in high

Boxed and palletized freight

Refrigerated van (reefer)

53 ft · ~98 in wide inside

Food, produce, pharma

Flatbed

48 or 53 ft · 102 in · ~5 ft deck

Steel, lumber, building materials

Step deck

48 or 53 ft · lower deck ~3.5 ft high

Taller machinery and equipment

Lowboy / RGN

Deck often under 2 ft high

Heavy and tall equipment

Tanker

Capacity varies by product

Fuel, chemicals, food liquids

Car hauler

Open or enclosed, multi-level

New and used vehicles

End dump

Bed sized by cubic yards

Aggregate, dirt, debris

Hotshot gooseneck

Often 30 to 40 ft, pickup-pulled

Smaller, time-sensitive loads

Power only

No trailer of your own

Pulling pool and shipper trailers

26 ft box truck

Up to 25 ft 11 in inside

Regional and final-mile freight

The one number to remember: a semi trailer can be up to 102 inches (8 ft 6 in) wide on the National Network. That limit shapes everything from pallet patterns to which loads need oversize permits.

How to choose a trailer type

Before the list, the questions that decide which trailer fits a business:

• What freight runs in your lanes? Van freight is everywhere; open-deck and tanker freight clusters around industry.
• How is it loaded? Docks and forklifts for vans, cranes and side-loading for open decks.
• Does it need temperature control? That's a reefer, with its own fuel and maintenance costs.
• How much do you want to invest? Specialized trailers cost more and need more skill, permits and insurance.
• Do you want to own a trailer at all? Power only skips the trailer and pulls someone else's.

The main types of truck trailers

1. Dry van

An enclosed box with swing or roll-up doors at the back. It carries most palletized and boxed freight: retail goods, packaged food, paper, parts. A typical 53 ft van is 102 inches wide outside, with about 101 inches between the walls and around 110 inches of height inside on one manufacturer's spec sheet.

• Suits: most new carriers; the biggest load market on every board
• Pros: dock-friendly, weather-proof, easy to load and secure, huge freight base
• Cons: the most competition on rates; height and door openings limit tall freight

2. Refrigerated van (reefer)

A dry van with insulated walls and a refrigeration unit on the nose. Insulation makes it a few inches narrower and lower inside than a dry van. Reefers haul produce, meat, dairy, frozen food and pharmaceuticals. Running costs include reefer fuel and unit maintenance; see reefer units.

• Suits: carriers who want steadier freight and can manage temperature records
• Pros: often pays more than dry van; can also haul dry freight when needed
• Cons: more expensive trailer, reefer fuel, temperature claims risk

3. Flatbed

A flat, open deck with no sides or roof, usually 48 or 53 feet long and about 5 feet off the ground. Freight is loaded from the sides or top by forklift or crane and secured with straps, chains and tarps.

• Suits: experienced drivers comfortable with securement and tarping
• Pros: carries what won't fit in a box; strong demand from construction and steel
• Cons: physical work, weather exposure, securement rules and cargo damage risk

4. Step deck (drop deck)

A flatbed with a short upper deck over the fifth wheel and a longer lower deck behind it, roughly 3 to 3.5 feet off the ground. The lower deck lets taller freight stay under the height limit without permits.

• Suits: carriers hauling machinery and tall loads
• Pros: more legal freight height than a flatbed
• Cons: less usable deck length; loading ramps sometimes needed

5. Lowboy and removable gooseneck (RGN)

Very low decks for heavy equipment like excavators. An RGN's front detaches so machines can drive on. Many lowboy loads are oversize or overweight and run on state permits.

• Suits: heavy-haul specialists
• Pros: high rates for specialized work
• Cons: expensive equipment, permits, escorts and route planning

6. Tanker

A cylindrical tank for liquids or dry bulk: fuel, chemicals, milk, cement. Hazardous liquids need a hazmat endorsement and placards. Liquid surge makes driving technical.

• Suits: drivers with tank and hazmat endorsements
• Pros: steady, specialized freight
• Cons: strict safety rules, cleaning between loads, endorsements required

7. Car hauler

Open or enclosed trailers with one or more levels for vehicles, from 3-car wedges pulled by pickups to 9-car stingers.

8. Dump trailer

End dumps and belly dumps for aggregate, dirt and demolition debris, priced by the load, ton or hour in local markets.

9. Hotshot gooseneck

A flatbed gooseneck pulled by a heavy-duty pickup, usually 30 to 40 feet. Hotshots haul smaller, time-sensitive loads. Many run under the CDL weight thresholds, which also changes the rules that apply.

10. Conestoga and curtainside

Flatbeds or step decks with a sliding tarp system or side curtains. They protect freight like a van but load from the side like a flatbed.

11. Intermodal container chassis

A frame that carries a 20, 40 or 53 ft shipping container between ports, rail ramps and warehouses. Drayage and intermodal carriers pull them, usually under an interchange agreement.

12. No trailer: power only

Power only carriers own a tractor and pull trailers that belong to shippers, brokers or other carriers, often preloaded at drop yards. It's the cheapest way into trucking equipment-wise; what power only is explains it, and power only loads shows how the freight is found.

Comparison table

Legal limits that shape trailers

• Width: 102 inches on the National Network, not counting safety devices.
• Length: states must allow semitrailers of at least 48 feet on the National Network; most allow 53 feet, often with a kingpin-to-rear-axle limit, such as California's 40 feet.
• Height: there's no federal limit. States set it, mostly between 13 ft 6 in and 14 ft.
• Weight: 80,000 pounds gross on the Interstate, with axle and bridge formula limits.

Check whether a load fits a given trailer with the dimension fit checker.

Semi truck and trailer terms

• Semi-trailer: a trailer with no front axle that rests on the tractor's fifth wheel.
• Tractor-trailer, semi truck: the tractor and semi-trailer together.
• Bobtail: a tractor with no trailer.
• Pup: a short trailer, about 28 feet, used in doubles.
• Stacked trailers: empty trailers loaded on top of each other to move them; see stacked trailers.

Parts and systems, from landing gear to gladhands, are covered in semi truck trailer parts, and where to keep a trailer between loads in truck trailer storage.

The 26 ft box truck is the smallest equipment we dispatch; we don't dispatch anything under 26 ft. Sizes in the chart are typical figures. Every trailer is built differently, so check the spec plate before you quote a load.