Everytime I make a turn, my car makes a really loud thumping noise somewhere in the back. I don't have anything in my trunk.

Does anyone know what could be wrong with my car?

Thanks for any advice.

 

Check for anything that is loose in your trunk, also I find that there is a thumping sound when the back seatbelts hit against the car's interior. Try securing the back seatbelts then turning to check, or make a turn in a parking lot and look in your rear view mirror to see what is going on.

 

Does it do it only when turning?

-Sheldon.

 

does it sound like it is coming from in front of you, or behind you? Can you tell?

Have you made any modifications to the front end? New tires or anything like that when this started? Check the wheel wells in the front. See if there is anything loose/hanging in there. Also check the inside of the tire (the side facing the motor). Do you see any wear marks?