A step-frame trailer is a type of trailer chassis where the deck height drops down behind the front section to create a lower main platform. This design allows for increased internal height, making it ideal for taller loads or double deck configurations.
The front chassis section — where the height drops down from the fifth wheel level — is commonly referred to as the swan-neck or goose-neck, named after its distinctive shape.
By lowering the main deck height, step-frame trailers optimise volumetric capacity. They are widely used for high-cube freight and in operations where load height is a key consideration.
