My wife has a 00 Z24 with the Auto 4speed Trans. Just recently it started making a clicking sound when the car is in gear, either forward or reverse. The sound is not present while in park. It still drives fine, just naturally concerned it is going to evolve into a larger problem. The sound doesn't have a predicatble rhythm, its always there but just sounds like something came undone and is bouncing around. The transmission has about 107K on it and i recently changed the fluid. I haven't checked the level since this sound came around but like i said, the car still drives fine. Let me know if anyone has any idea what it may be.