Below is a list of Differential Gears manufacturers from Saint Marys, Pennsylvania. Differential gears refer to an arrangement of gears that are used to transmit torque and rotation through three shafts. This type of gear is most commonly used in two ways. The first is to receive input and provide two outputs. The second is to combine two inputs to create an output that is the sum, average or difference of the inputs. The first way is the most common and is typically used as rear end gears in cars, trucks, other self-powered vehicles and industrial machinery requiring perpendicularly transmitted torque.