On my way to Emerald Isle North Carolina from Baltimore the dreaded milling sound appeared in my last hour of the drive. Prior to that I got a vibration on hard acceleration — that’s been there for about a month. Assume the drive unit has a major problem and will have to be replaced. I’m here for two weeks on vacation, so not much driving to do. But I have a near 400 mile trip home. What are the odds that the drive unit will fail leaving me stranded? What advice would others give to avoid a failure of the DU?