Ford Racing 04-17 F-150 4x4 8.8inch Front Axle Limited Slip Torsen DifferentialsThese Ford Racing Torsen differentials use a worm gear friction system that will not wear out like conventional clutch type positive traction differentials. These differentials ensure your engine's power is transferred to the wheels with the maximum traction. The unique torque sensing ability of the Torsen design, and the smooth engagement of Torsen style limed slip differentials, make them the perfect choice for your street, strip, or off road