My '99 Forester has a rear-end humming noise, almost like worn sticky tires, directly related to speed. At 40mph it becomes audible, at 60mph it's fairly loud. Weird thing is, I just drove the car last week and the noise was not pronounced enough to notice.
Since it's Sunday the only people willing to look at it was Sears, and they say it's not the wheel bearings, it's the rear differential. The only evidence against their theory is: when you put it in neutral at speed (it's an auto), the noise stays.
1999 Forester, 113,400 miles, never had wheel bearing or diff issue.
Anybody with stories of how their dead wheel bearing or diff sounded greatly appreciated.