Make your own Gasket
Mobil 1 is fine for differentials and for the transfer case I have used it with no problems.
Transfer case holds 2 Quarts
Front differential holds 3.7 Pints (75w-90)
Rear differential holds 5.5 Pints (75w-140)
Also get 1 bottle of friction modifier for the rear differential
2005 5.4L Lariat 4x4 SCREW, 3.73LS, BFG All-Terrain 275/70/18, Bilstein 5100's, Banks Cold Air Intake, Banks Monster Exhaust, Banks Sport Tune or Towing Tune