Drive the car with the windows up and everything off to ensure the transmission is not making noise. Make sure all four tires are equal in tread. If not this will cause issues with the awd system and you may end up replacing a center diff later on down the road. Turn full lock in a circle make sure there is no binding, you feel a lot of binding/resistance in the drivetrain the center diff is probably going. Check the oil and diff fluid. Does it smoke? Look down in between exhaust and tranny to see if axle boots are torn, the same for the drivers side as well.