A whining noise may occur as a result of low power steering fluid, a transmission problem or bad wheel bearings. The most common transmission problem that causes a whining noise is low transmission fluid.
If power steering fluid continues to go low, check for a leak by looking underneath the vehicle for wetness. With the transmission, if low fluid is not the culprit, it could be severe wearing of the bearings and gears of the transmission system. To look for wheel bearing wear, look at the tapered rollers because they become barrel-shaped during the wearing. The bearings will not have a polished finish, either.