Noisy in gear but goes away out of gear.
 

2001 TC 3.8 FWD

Stopped by to see my parents and they have the above vehicle. There is a rattle type sound seems more pronounced on the passenger side of the engine. I did lift the hood to listen to it as my mother went thru the gears. Does not go away when stepping on gas.

This rattle only happens when the vehicle is placed in gear and not in neutral or in park. That means each gear, 1st thru reverse.

Any thoughts? Sounds like a muffled can of bolts rolling around. The torque converter was replaced once I believe.