What is a Double Drop Trailer? A Guide to Oversized Freight Transport

Understanding Drop Trailers

When you’re moving oversized or tall freight, a standard flatbed won’t always cut it. That’s where a double drop trailer, also known as a double drop flatbed or double drop deck trailer, comes in.

Built to haul freight that exceeds standard height limits, double drop trailers offer the clearance and support needed to keep loads compliant and on the move.

Its key feature is the lower center deck, also called the main deck or “well”, which allows for increased vertical clearance.

This double drop design is perfect for hauling tall freight such as:

Construction equipment
Heavy machinery
Power units
Tanks or oversized industrial equipment

By sitting lower to the ground, double drop trailers accommodate height-sensitive freight while maintaining load stability and compliance with DOT height restrictions.

Double Drop Flatbed Trailer Overview

Double drop trailers go by several names:

Double drop flatbed
Double drop deck trailer
Double drop step deck
Double drop lowboy trailer

While naming varies, they all refer to trailers with a front deck, a low center well, and a rear deck positioned over the axles.

Their design allows for:

Hauling tall freight up to 11’6″ without permits
Better load distribution for heavier equipment
Flexibility in securement, especially for irregular loads

Double Trop Trailer Dimensions & Specs

Understanding trailer dimensions is critical when planning a shipment. A standard double drop trailer typically includes:

Length: 48′ to 53′
Width: 8’6″
Main (well) deck height: 18″-22″
Maximum cargo height (without permit): Up to 11’6″
Weight capacity: 35,000-40,000 lbs, depending on axle setup and materials (steel vs aluminum)

If your freight is tall and extremely heavy, a double drop lowboy or double drop RGN may be more suitable. However, when vertical clearance is the main concern, double drop trailers strike the right balance between capacity, compliance, and cost.

Anatomy of a Double Drop Trailer

Double drop trailers are built with three main decks:

Front Deck: Located just behind the tractor. Often used for smaller tools or gear that doesn’t require additional height.
Main Deck: The lowest part of the trailer, sitting only 18 to 22 inches off the ground. This area supports tall or heavy duty cargo like cranes, transformers, or excavators.
Rear Deck: Supports the axles and provides ramp access or extra space. Some carriers may install a rub rail to create more securement points across all decks.

The combination of deck levels allows shippers to safely transport complex or bulky equipment using a single trailer configuration.

When to Use a Double Drop Flatbed

A double drop trailer is the right fit when your freight:

Exceeds the legal height limit for flatbeds or step decks
Doesn’t require drive-on access (ideal for crane or forklift-loaded cargo)
Has an irregular shape or needs securement flexibility
Is tall but not excessively heavy (under ~40,000 lbs)

These trailers are engineered to accommodate tall, wide, or irregular cargo without needing custom builds or permits in many cases.

Industries that rely heavily on double drop trailers include:

Construction (cranes, excavators, cement mixers)
Agriculture (tractors, sprayers, harvesters)
Energy & Utilities (transformers, turbines, tanks)
Manufacturing (industrial machinery, generators)

If your shipment exceeds height limits on a standard flatbed or single drop trailer, a double drop deck can help carry the load safely while remaining compliant with state and federal laws.

Double Drop vs. RGN vs. Lowboy Trailers

Each of these trailer types is used for over-dimensional freight, but they serve slightly different purposes.

Feature	Double Drop Trailer	RGN (Removable Gooseneck)	Lowboy Trailer
Neck Type	Fixed	Detachable (allows drive-on access)	Fixed or detachable
Best For	Crane-loaded or forklift-loaded equipment	Wheeled/tracked machines (drive-on)	Extremely heavy and tall loads
Max Height (No Permit)	~11’6″	~11’6″	~11’6″-12′
Cost	Moderate	Higher (due to complexity and detachable design)	Varies – can be high depending
Use Case	Tall machinery that doesn’t require drive-on	Dozers, lifts, large rolling equipment	Very heavy, high-value construction equipment

Both double drop trailers and removable gooseneck trailers (RGNs) serve the oversized cargo market—but there are key differences based on how the freight is loaded.

Double Drop Trailers

Best for crane-loaded cargo
Lower cost when drive-on access isn’t needed
Fixed neck and simpler structure

RGNs

Feature a detachable front deck (gooseneck) for drive-on loading
Ideal for wheeled or tracked equipment like dozers or lifts
May extend to fit longer equipment

The right choice comes down to your equipment and loading method. If you can crane-load your cargo, double drop may be the most cost-effective and simple option. If your freight needs to be driven onto the deck, an RGN trailer is the better fit.

What Is an Open Deck Trailer?

An open deck trailer refers to any trailer without an enclosed structure, allowing freight to be loaded from the sides, rear, or top.

Types of open deck trailers include:

Flatbeds
Step decks (drop decks)
Double drop trailers
RGNs
Lowboys

Double drop flatbeds fall into this category and are specifically designed for hauling freight that requires additional vertical space.

Choosing the Right Partner for Specialized Freight

When moving tall, oversized, or irregular freight, working with an experienced logistics partner makes a difference. A qualified partner can:

Select the right trailer configuration (double drop, RGN, lowboy)
Manage permits and routing for over-dimensional freight
Use correct securement methods and equipment
Help reduce risks and delays

To get a quote, be prepared with:

Load dimensions (length, width, height)
Weight
Pickup and delivery locations
Loading method (crane vs drive-on)
Equipment or commodity being hauled

Final Thoughts

A double drop trailer is an essential tool for safely moving tall freight while staying compliant with DOT height limits.

Need help planning your next over-dimensional shipment?

ShipEX Logistics offers specialized solutions, including double drop trailers, lowboys, and RGNs, to move your freight safety and on time.

What Is a Double Drop Trailer?