Abstract: The invention is a set of reduction gears constructed to aid the installation or removal of a packing nut or similar equipment part onto or from an oil field pump. A first gear is integrated onto a packing nut or other threaded part to a piece of oil field equipment. The first gear is placed in rotational contact with a second gear rotatably mounted on the surface of a fluid end. The second gear is a reduction gear which a worker can turn to thread the first gear of the packing nut. The invention includes a pawl set against the first gear prevent unwanted loosening of the packing nut during operations.