At the same time, it couldn't hurt to change trans fluid and diff oil at the same time.
Trans (manual) gets 80W 90 GL4 only. Must be GL4 or listed as yellow metal safe.
Auto (if you have it) I think uses a Dex/Merc
Diff gets 80W 90 GL5.
Couldn't hurt to check the bearings for play, and steering components (center link, tie rod end, pitman arm, etc) for play. You might be surprised what's worn out.
Also adjust your dear drums, and remove the slack from the parking brake cable. I'm sure it's stretch and probably hasn't been adjusted in years.
Pretty sure everyone's covered everything else.