car started to make some loud resonant noise from the back, under the car during the winter and stays till now. car is almost 80k miles. it sounds only @ very low speed or idle like backing out of the driveway situations with moderate throttle position. anyone?

 

exhaust leak?
exhaust hanger problem? like bent arm so the exhaust is touching some part of the chassis?

 

what kinda cat you got? and im not talking about kitty cats

 

oh sorry, forgot to mention. my car is still in stock condition. but well maintained