There are lots of noises that come with operating a vehicle, from the hum of the fuel pump to the whine of a supercharger. The whistle of the turbocharger or the quiet roar of the tires on the pavement they are all sounds we get accustom to. The one sound that is common that most of us cannot stand is a belt squeal. The noise is created either by the belt in the groves of the pulleys in which it rides. There are a few different causes can be associated with the source of the squeal. When the sound comes after a rain or driving through a large puddle it means that some of the water has reached the back of the belt and is causing slippage which is the source of the sound.
Belt squeals are caused by the belt not being tight enough and slipping on the pulley, when the rubber of the belt slides on the pulley it causes the sound. A huge concern on this is that the belt will wear faster and could snap leaving the drive of the vehicle stranded.
Belts become loose for a few reasons in a vehicle, one is that over time the belt has stretched due to tension. Another factor can be physical movement of the belt driven part itself, all belt drive accessories are bolted to the motor on sliders. If the bolts that hold these units become loose the belt tension will lower and slippage will occur.
Belt squeals can be fixed in a number of ways, a new belt can be installed and the problem will be solved though this can be expensive at times. The more popular solution is to just simply tighten the belt, this is a simple process of loosening the bolts that hold the accessory causing the sound and moving the unit till the belt is tight. Then secure the bolts and the sound should be stopped, it is important to not over tighten the belt as too much tension can cause the belt to snap. As with all car maintenance it is important that this be done properly by someone who knows that they are doing. With proper attention a car can last well into the half million mile marker without major issues.