The V8s must be different. Mine is right next to the front diff breather where Uneek described also. I have a V6 though.
Sorry this doesnt help at all, but just throwing it out there.
Edit-This is a quote I found from a google search. It came from this site though. It may or may not help.
"As an addendum, you can find the breathers for the transfer case and transmission on the 04 V8 hiding between the firewall the inlet manifold directly above the location where the transmission mates to the block. You need to climb up on top of the engine to find it. With a torch you can see the white or silver valve.
By approximation, it would be only 2-3" lower than the front diff breather."