Below is a list of 12v Hydraulic Pump manufacturers from Grand Rapids, Michigan. 12v hydraulic pumps are hydraulic power units that run off of 12 volts of direct current provided by a battery or motor. Like all hydraulic pumps, these are specially designed mechanisms used in industrial, commercial and consumer contexts to convert kinetic energy into useful mechanical energy via the pressurization of viscous fluids. This converted energy is used in a number of industries.