A trailer having a storage container, a landing gear assembly coupled to the storage container, and a rear wheel assembly coupled to the storage container includes a side skirt system for reducing drag on the trailer. The side skirt system includes a side skirt wall configured to be coupled to one side of the trailer to extend below one side wall of the trailer at least partially along a length of the trailer. A length of the side skirt wall along a top edge of the side skirt wall is approximately 48%-80% of a distance between the landing gear and forward-most position of the rear wheel assembly.