I wish it was an easy fix. Pinion bearings are really really bad, so I'm expecting the ring and pinion gears are fucked. NOS 4.56:1 gears are expensive. Then need a case spreader to get the diff out of the case and that's an expensive tool that I'd never use again. Special clamshell bearing puller is expensive, that I'd never use again. Either way it an expensive fix. Wife doesn't know how much yet... shhhh!