My 9-5 has about 177K miles on her. Last night whilst exiting a parking lot, I hear a loud THUNK; it reminded me of the sort of sound you might hear if you drove over a high curb and the curb hit the bottom of the car. When I got home, I noticed that the rear end of the car is sitting much lower than normal. I am bracing myself for what may be a pricey repair. I don't even know if my model has rear shocks (I believe there are shocks in the front). Anyone have any ideas on what may have caused this?