I'm new to Camaro Forums. I recently purchased a 1998 Z-28 with a lot of highway miles (160000). The car was owned by a lady who commuted a long way to and from work, other than the milege the car is in exellent shape. There is a bumping noise in the rear and can be heard on the slightest bump. I think the rear hatch latch needs to be adjusted but the noise seems to be under the car. I have checked underneath and cannot find anything visibly loose. Also I want to know a good muffler to replace the stock one with, not to loud but one that will give good flow and sound. Any information on the issues will be appreciated.