I brought my new '03 Cobra Mustang to Ford due to a persistent whine in the drivetrain that is audible at the 40-45 mph range and again above 70, particularly at neutral to slight throttle loads. They replaced the entire differential which did no good. Today I was told that Ford engineering folks believe there is a potential problem with the "cut" of the gears for these 3.55 differentials, but they won't replace mine again unless they actually have a fix. They told me to check back with them in six months or so. The area engineer they sent out said he has driven other cobras, and they all made the same slight whining noise. So guys, what do I do now to protect my rights? I don't think I should have to live with a situation like this after spending $34000 on a car? Who do I contact and how? I'm sure if I just sit back, nothing will happen! HELP!