In my 2.4L 2000 Pontiac Sunfire GT, when I drive I hear a "clunking" sound coming from what seems like the right rear tire area. This noise does not happen all the time. It seems like it only happens when I first back out of my driveway in the morning and then for a little while after. Then it goes away. Then it may return later in the day after not having driven it for a few hours. It is nothing in the trunk, I looked inside and the spare tire and everything is secure. It is too loud to be a light bulb or anything or the sort. It is not the drum or anything with the brakes because I just put new rear shoes on it and made sure everything was 100% secure. Any ideas? Suspension issue?