My vehicle is making a noise like a flat tire but no flat tire it is the loudest when my foot is off the gas and im coasting I have had the bearing checked that is not the problem of course the mechanic couldn't hear it when he took it out but as soon as I left it started doing it they also told me the motor mounts are a bit loose but they didnt give me much information on it they kinda rushed me out my car is also vibrating quite a bit anyone have any thoughts on what it could be