Abstract: A collapsible platform assembly secured to a hopper of a sanding truck allows an individual to safely observe and/or facilitate the loading of the truck hopper. The platform is pivotally mounted to a side of the hopper and is driven by an hydraulic actuator, powered by the hydraulic system of the truck, between a substantially horizontal, operational position, and a substantially vertical, storage position. The platform assembly also includes an integrated collapsible railing, an automatic lighting system to illuminate the platform area when the platform is in its operational position, and a warning indicator within the truck cab which is activated when the platform is not in its storage position.