A deployable hay pod elevator system for a transport trailer, such as a livestock trailer, provides a readily deployable hay pod, storage pod, or supply platform with the trailer, and is readily stowable above the trailer in a raised configuration for travel. The elevator system includes a deployable supply platform and a vertical raising and lowering mechanism or lift system configured to move the supply platform relative to the trailer. The lift includes a pivot arm system coupled to a sidewall of the trailer and a lift assist mechanism, such as a linear actuator, to vertically raise and lower the deployable supply platform. The elevator system includes a supply platform pivot actuation mechanism to adjust the angle of the platform relative to the pivot arm during stowage and deployment of the system. The elevator system may be fitted to various types of vehicles to store and transport various materials.