Well, with mine, driving at 40mph on a smooth quiet surface, I can press the gas pedal slightly, and get a creak, and release the gas pedal and get an equal and opposite creak. This is not even hard acceleration, so I would expect the body to have less flex than that. At any rate, I've installed a nicer stereo, that I can play louder, so when the dealership replaces my broken interior panels, if it still creaks, I'll try to ignore it by blaring tunes over the top. Maybe removing the resonator on the exhaust, and adding a needswings intake would help drown out the sound. Maybe even ASP pulleys.