Yukon Gear Ford 9in Differential w/Trac-Loc LSD Dropout Assembly 31 SplineYukon dropout assemblies are built by expert Yukon technicians and come complete, properly shimmed and backlashed to spec. All you do is install the third member into your diff housing, bolt on the diff cover, add fluid, and roll. This unit features a nodular iron case which improves rigidity and power handling, reducing deflection for consistent gear contact and a long service life. This assembly is upgraded with a Trac Loc limited slip differential