Why Would a Car Make a Whining Noise?
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.
Whining noises are associated with belt problems throughout the engine. The variety of belts in an engine compartment makes it difficult to tell which one is whining without visual inspection. Turning the car on and lifting the hood shows how the belts are running and is a good indication of which belt needs to be shifted, adjusted or replaced.
The most likely belts that cause whining in an engine are the cam shaft belt, fan belt, timing belt or tensioner. These belts hold the engine together and keep the entire car running properly, so the loss of one greatly harms the function of the rest of the machine.
Visually inspecting belts shows whether they are running properly over the gears where they are set. When these two elements are not properly aligned, the belt sliding off the wheel or causing unintended friction creates a whining sound. This also wears down the belt prematurely and results in the potential for the belt to snap while driving.