I thought my pinion seal was leaking. However, the oil seems to be coming from around the pinion nut. How do you stop this? '96 F150 w/8.8 rear end

 

It is pinion seal. Unless there is a seal right behind the nut. But I do not see one listed behind it. If you pull it apart, replace all the small parts listed for it. The differential yoke has a good price tag. The bearings, seal, deflector, the nut, spacer, and the slinger are all cheap. Also hope the ring and pinion shaft is good also.