The phrase "trailas de carga usadas" is Spanish for "used cargo trailers." It covers everything from used utility trailers to cargo trailers large enough to require a semi-truck. Consumers hear the phrase mostly in areas with large Hispanic populations, as well as in countries where Spanish is the first language.
Well known companies such as Ryder Truck Rental often offer used trailers and other vehicles for sale. They have Spanish language pages that bring their goods to a wider customer base. For example, Ryder sells used trucks, tractors and trailers on its Vehicle Sales page. On the Spanish page, accessed through a link at the top, Ryder lists used panel trucks as "camionetas de carga usadas" while larger cargo trucks are "camionetas urbanas usadas." The word "usadas" or "usados" means used.
Ryder Trucks also offers the larger trailers, and breaks them down into different categories, all with the word "usados" in the description. Semi trailers are "semi remolques usados," and refrigerated trailers are "remolques usados con refrigeration." Platform trailers are "remolques de plataforma usados."
Smaller trailers have the feminine form of "usadas," while the larger rigs usually use the masculine form of the word, or "usados." It is common in the Spanish language to assign gender to items.