We used a genuine Lube Locker gasket because of its superior sealing technology. Once you try these, you probably won't ever use silicon sealant again. These reusable gaskets are packed with innovations that vastly increase sealing ability. Each gasket features a rubber-coated steel core that is lined on both sides with a special orange elastomer beading that seals the perimeter and each bolt hole. This arrangement virtually eliminates any possibility of a leaky differential, even if the cover smacks a rock and shifts slightly.