How do I take the rear end apart to see the gears? on 2002 Nissan Xterra

I'm trying to get the covers off the rear end to see the gears, my truck feels like it's slipping gears. Do I have to remove the axels to see this?

Asked by for the 2002 Nissan Xterra
You don't need to remove the axles in your rear differential to see the gears but if your truck feels like it's slipping when shifting than the gears you need to be inspecting or I should say having inspected are the gears in the transmission!