Draining & Refilling: Differential
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 1991 Toyota Tercel, 1991 Toyota Supra, 1991 Toyota MR2, 1991 Toyota Cressida, and 1991 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
Some FWD models have separate drain plugs for transmission and differential. Both transmission and differential plugs must be removed to drain all fluid from both units. Transaxle is filled through dipstick tube, and differential is filled through a separate fill plug. See Fig 1. Fill differential until fluid is level with fill hole.