The typical life of a serpentine belt is about 60,000 miles or five years. When the belt nears the end of its life, it may become cracked, glazed or noisy.

If an aging belt or tensioner is not replaced, the belt could break, causing a loss of drive torque to all of the engine's accessories. This can cause major problems. The water pump in many cars is driven by the serpentine belt, if the water pump stops turning, the flow of coolant stops and your car could overheat. When your alternator stops turning, there is no charging output and the battery starts to run down. When the power steering pump stops turning, the steering suddenly gets stiff and very hard to control.

On many occasions an old serpentine belt will be replaced with a new one, but the automatic tensioner is not inspected to make sure it is working properly. This mistake can lead to rapid belt wear and repeat failures if the tensioner is weak or worn out.

Symptoms that could indicate your belt tensioner is worn include:

Belt Slipping (due to loss of tension)

Belt Glazing (caused by belt slipping)

Wobble in tensioner pulley (possible bad pulley bearing)

Excessive noise coming from the tensioner.

How do I check my belt tensioner?

Check the movement of the tensioner arm with the engine off. (If your car is equipped with an electric fan use caution) Some fans can turn on without the engine running) Use a socket with a long handle ratchet on the tensioner pulley center bolt to rotate the tensioner. There are no specifications for measuring the amount of resistance offered by the tensioner spring, but if the tensioner offers little or no resistance it may indicate a weak or broken spring. If it fails to move at all, the tensioner is jammed and needs to be replaced. In most cases this is generally an easy repair to do at home.

DIYautoparts.com carries a full line of serpentine belts and tensioners. If you have any questions about replacing either your serpentine belt or tensioner, please feel free to contact one of our automotive experts at 1-800-593-1443 or 1-315-437-7696. We will be happy to help.