Hi I'm new to this so if I don't make sence bare with me. I have a 2002 cavilier. When I reach around 40mph I start to hear a sound that I can only describe as a hollow sound. I have no maintance problems this has been going on around ayear a half. Have trav

eled from Georgia to Florida several times. This sound is starting to reallllly anoy me. I was told it may be the tire but don't know for sure. I think it sounds like the exhaust but I'm just a girl!!! and don't not squat about cars. Can someone help?
Lisa