Yukon Gear Dropout Assembly for Ford 9in Differential w/Grizzly Locker 31 Spline 3.50 RatioYukon 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 Yukon Grizzly Locker for maximum