What is causing the strange noise in the back when the car reaches around 40mph?
I just bought the car; it has 57,000. On the way home from the dealership when we got off the freeway and back to city driving, the car made a noise as if it was adjusting- it sounded robotic. Now, as we drive through the city, it happens all the time, right around 40 mph. There are no warning lights showing up. Should we be worried?