Replace it. Your tranny calls for Mercon ATX fluid. Use Mobil 1.
A good rule of thumb, even though not in print is to change it as often as you would an auto tranny... every 50,000km. But yes for sure!!!! at 100,000km.
You will feel a difference


Former 1998 SE V6 Contour owner Presently Sentra SE-R SpecV