5. The TA Performance cover is a functional work of art. The two Allen-head load bolts have feet that support the carrier bearing caps between cap bolts. Under high torque loads, unsupported caps can distort. When that happens, the "pin" just got pulled on that axle's "grenade." In addition to adding a considerable amount of beef to the center housing, the TA Performance cover adds about an extra pint of oil capacity, helping the diff run cooler. The cover is complete with a drain plug and a high filler plug. We also ponied up for the optional bearing cap stud kit, which replaces the carrier bolts with aircraft-grade studs and nuts.