Hi All. Our 2001 Mercedes 320E developed a rattle that seems to come from underneath the car. It only rattles when in gear; not when in park. I checked the transmission oil and it is fine. No fluids leaking on the floor. It has only 75K miles and has been running fine. PLEASE LISTEN TO THE RATTLE and LMK what you think the cause might be. Thank you. Here's the sound file: C:\Users\ronal\Dropbox\Car Noise.wav

 

to me it sound like cat. Probaly need to raise the vehicle and find your problem.