This thesis was performed at Zetterbergs Industri AB. Zetterbergs is designing, building and mounts body systems for trucks, including dumpers and tippers. The assignment for the thesis was to design a door hinge for a spreader gate. The spreader gate is the top of the two tailgates on a dumper or tipper and opens back and outwards when tipping the cargo. The spreader gate controls the mass flow of the material being tipped.