The creaking in the headliner that you are talking about, does it kind of sound like styrofoam on styrofoam rubbing. Our '04 is making a sound like that on cooler days right behind the driver side vent in the back seat. It was really bad this last winter. The roof had a little bit of ice on it and I thought it was that, but the noise persisted even with a clear roof. Also, we went on a road trip last fall along a two-lane road and used the sport-mode 4th gear for engine braking on the long descents. The trans would hold that gear for a while, then kick out, touch the gas and it'd kick in for 10 seconds, then cut back out. Took it to the dealer for our $67 free oil change, asked them about it, said it was normal. 3rd holds back fine, though.