My tranny did the same thing. I thinks it's a 999(?)3-spd. auto. I dumped a couple of doses of Lucas in it, and it straightened up. Hasn't been a problem since. Your results may vary.
Corona


'98 TJ, 4 cyl., auto
31" AT KO's on rockcrawlers,
custom bumpers, Hellas
2" Teraflex lift, no top,
no doors, no problem.