there is a tsb on slow turn maneuvers, it's the rear diffrential. I had that and the dealer fixed it by replacing something but i can't remember what it is.
Shifting noises, i have that too but i have no clue what it is. I told the dealer a couple of times but they said it was normal, go figure!! It might be the driveshaft because of the two piece design? i'll get back to you on that one when i'm sure.
do you get the vibration at high speed from brakes when braking? if so, i think it's due to the bad stock braking system, it's completly useless!!! try changing rotors, if that doesn't work change the whole of your front brakes. that's what i'm going to do when i save some $$$
06 Auto GT RedFire, 3dCarbon Boy Racer Kit (13 pcs), GT500 Spoiler, CS8 Shelby Hood, 20" Chrome Foose Nitrous, Steeda Carbon Fiber Dash Kit, C&L Street, Tillman Tune, Steeda UDP, Steeda CMDP, No Cats, Borla Mufflers, Tokico D-Specs, Rear Roush Springs, FRPP 4.10, PowerSlot Slotted Rotors, Hawk HPS pads