OTTO Swing Motor Assy 282-1534 for the Caterpillar E304 / E305.5 / E305 mini excavator - supplied as a complete swing motor assy, ready to fit. It mounts on the swing circle and turns the upper structure: hydraulic pressure drives the motor, which turns the upper frame through the swing reduction and output pinion. It is supplied as a complete unit, so the old assembly is unbolted and swapped. Send us the machine serial and the number on your old unit and we will confirm before dispatch. 3-12 months warranty options.