High Lift Door Projects High Lift Doors for a Mixed Fleet Dock China Project reference: High Lift Doors for a Mixed Fleet Dock. Customer Challenge A dock served both container trucks and smaller box vans, and drivers kept hitting the old standard-lift door. Our Solution We installed high lift doors with 4.5 m lift clearance so the door clears the tallest vehicle before any horizontal travel. Results Vehicle damage incidents stopped and the same opening now serves the whole fleet.