Prizm (Differential)
WARNING: This page is about a different car, the 1992 Geo Tracker and 1992 Geo Prizm. However, it is still accessible from the selected car via links, so may be relevant.
Remove drain plug in bottom of differential cover, and drain fluid. See Figure. Install drain plug, and tighten it to 29 ft. lbs. (39 N.m). Remove fill plug on side of differential cover. Fill with Dexron-II until fluid runs from fill hole. Install fill plug.