Semi-Truck Trailer Types, Dimensions & Capacity

The fast reference: usable height, weight capacity, and the freight each trailer is built for. Tap a name to jump to its full spec sheet.

Federal limits: 80,000 lb gross · 8′6″ (102″) wide. Height is state-set — 13′6″ in most states, 14′ in many Western states. Payloads shown are legal usable weight under the 80,000 lb cap — not trailer GVWR; actual payload depends on tractor weight. Sizing a partial or full load? Truckload Calculator · Linear Feet Calculator.

Enter your tallest item and total weight, flag refrigeration or open-deck loading, and we'll point you to the right trailer — using the same logic our quote wizard runs.

On an open deck, how tall your freight can be is simply the legal height limit minus the deck height. A lower deck buys more usable height under the same ceiling — which is exactly why step decks and double drops exist.

Fully boxed equipment that protects freight from weather and loads at a dock. The default for general and temperature-controlled freight.

Dry Van

The default for general freight — a fully enclosed box that protects almost anything that fits inside and doesn't need temperature control.

Inside length	52′6" (53′ trailer)
Inside width	8′3" (99")
Inside height	9′2" (110")
Door opening	~98" × 104" (W×H)
Cargo payload	42,000–45,000 lb
Pallet positions	26–30 (48×40)
Cubic capacity	~3,400–3,800 ft³

Roll-up (overhead) doors typically eat ~6" of interior width and a little height versus swing doors — worth checking if your load is wide or tall.

Refrigerated (Reefer)

A dry van with an insulated body and a front-mounted cooling unit — for anything that has to stay cold, frozen, or within a set temperature band.

Inside length	51′7"
Inside width	8′1¼" (97¼")
Inside height	8′7"–8′8" (104")
Temp range	‒20°F to 70°F
Cargo payload	~43,000 lb
Cubic capacity	~3,000–3,400 ft³

The reefer unit and insulation steal 2–5 ft of length in the nose and a couple inches all around — usable space is a bit smaller than a dry van, which is why payloads run lighter.

No walls or roof — load from any side or the top by crane or forklift. For freight that's oversized, very tall, or won't fit through a van's doors.

Flatbed

An open deck with no walls or roof — load from any side or the top by crane or forklift. The workhorse for building materials, machinery, and anything that won't fit in a van.

Deck length	48–53′
Deck width	8′6" (102")
Deck height	~5′ (60")
Max freight height	~8′6" (102") legal
Cargo payload	46,000–48,000 lb

There's no roof, so legal height is the only ceiling: ~8′6" of cargo on top of a 5′ deck reaches the 13′6" road limit. Open freight must be tarped and strapped/chained.

Step Deck

A flatbed with a lower main deck (and a short upper deck near the nose). The drop lets you haul taller freight than a flatbed without a permit.

Lower deck length	37–42′
Upper deck length	10–11′
Deck width	8′6" (102")
Lower deck height	36–42"
Max freight height	~10′ (120") legal
Cargo payload	44,000–47,000 lb

Also called a "drop deck." The lower deck sits about 18" below a flatbed, so freight up to ~10′ tall still clears the 13′6" limit. Heavy equipment can be forklifted or ramped on.

Lowered decks that keep tall, heavy machinery under the 13'6" road limit. When a flatbed or step deck isn't low enough, these are next.

Double Drop

A deck that drops to a low well in the middle, between a raised front deck and the rear axles — for the tallest freight that still moves on standard equipment.

Well length	24–30′
Deck width	8′6" (102")
Well floor height	18–24"
Max freight height	~11′6″–12′ in the well
Cargo payload	~40,000 lb (up to 44,000)

The center well sits low to the ground, so tall freight rides under the legal ceiling. Freight is loaded into the well by crane or forklift; very tall/wide loads may still need a permit.

RGN (Removable Gooseneck)

A double drop whose front gooseneck detaches and lowers the deck to the ground as a ramp — so heavy machinery can drive or roll straight on.

Well length	26–30′
Deck width	8′6" (102")
Well floor height	18–24"
Max freight height	~12′ (144") in the well
Cargo payload	40,000–44,000 lb (more with added axles)

The detachable front lets the deck drop to ground level so equipment drives on under its own power. With extra axles (flip/jeep), RGNs carry far heavier loads, but those move under permit.

Purpose-built options for weather-protected open freight, tight urban deliveries, and moves where you bring your own trailer.

Conestoga

A flatbed or step deck fitted with a retractable rolling tarp on a frame — open-deck loading with the weather protection of a van.

Length	48–53′
Width	8′6" (102")
Usable height	96–102″ (up to ~110″ on a step-deck base)
Cargo payload	42,000–44,000 lb

The rolling "wagon-top" tarp opens from either side or retracts fully for crane/forklift loading, then seals the freight from weather — no tarping by hand. The frame costs a little capacity versus a bare flatbed.

Straight / Box Truck

Cab and cargo box on a single chassis (no separate trailer) — smaller and far more maneuverable than a semi for city and limited-access deliveries.

Box length	12–26′
Box width	8′ (96")
Box height	8–9′ (96–108")
GVWR	26,000–33,000 lb
Cargo payload	~10,000–12,000 lb

Heads up: the headline weight on box trucks is usually GVWR, not payload — a 26′ non-CDL truck is ~26,000 lb GVWR but only carries ~10,000 lb of freight. One unit also means a tighter turning radius and easy access to lifts and tight streets; often paired with a liftgate where there's no dock.

Power Only

Just the tractor — you supply the trailer or container. For drop-and-hook moves, repositioning equipment, or pulling your own assets.

Equipment	Tractor unit only
Cab types	Day cab or sleeper
Pulls	Your van, reefer, flatbed, or container chassis
Typical use	Drop-and-hook, container drayage

There's no trailer to spec — capacity and dimensions are whatever equipment you provide. Confirm the tractor's fifth-wheel/kingpin and any required endorsements match your trailer.

Trailer choice is mostly about keeping a load legal. Stay inside the limits below and any carrier can haul it; cross a line and you're into permits, escorts, and specialized equipment.