I see mention of an inner seal next to the sixth pic down on this page:

http://www.4x4wire.com/toyota/maintenance/front_end/teardown

and mention of another inner seal here next to the ninth pic (after removing the 3rd member):

http://www.4x4wire.com/toyota/maintenance/front_end/solid_axle

Is there a way to figure out which one is leaking without disassembling the entire axle? I'm betting everything is leaking due to the age of the truck. This ought to be fun!

Thanks for the links.