I just bought a friend's c320 because he was moving and I owed him a favor. I was also in the market for a spare vehicle. It has 104000 miles on it and runs very strong. When I had it smogged, it was the cleanest car the tech had ever tested. That said, it has a slight whine in the differential at around 40mph that dissipates with speed. the rear suspension seems a little skittish as well. Did I just make a serious mistake by taking on this car? i just need it to be reliable to drive 100 miles a week or so. Thanks for any input...