Forklift-Compatible Hydraulic Stationary Dock Leveler - Strength Steel Platform Automatic Hydraulic System for Truck Container Product Overview Driven by hydraulic assemblies, the stationary hydraulic dock leveler functions by using a main cylinder to lift the platform and a smaller auxiliary cylinder to actuate the lip plate. When the lip plate lies naturally on the truck bed, it forms a smooth connection between the dock and the vehicle, optimizing the whole loading process