which differential fluid?

[Pathfinder995]

I have a 99.5 Pathfinder SE and I want to change the rear differential fluid and use an Amsoil product. 1) has anybody used Amsoil gear fluid in their differential?2) did it improve performance? 3) what weight of oil did you use? it seems like 80w90 is what's called for in most cases.

Also, has anybody used Amsoil's ATF transmission fluid in their transmissions? Same questions as above...performance better?

-Jeff

[fueler]

yeah its 80w90 but i use pennzoil