Symptoms of a bad or failing serpentine/drive belt

The serpentine belt, also known as the drive belt, is a belt on a car engine that works with the idler, tensioner, and pulleys inside the accessory drive belt system. It provides power for the air conditioning, alternator, power steering, and sometimes the cooling system water pump. The serpentine belt is a critical part of this system, and once the engine is running, it continues to operate until the vehicle is shut off. Without a properly functioning serpentine belt, the engine may not run at all.

As a general rule, a serpentine belt lasts up to 50,000 miles or five years before it need to be replaced. Some can even last for up to 80,000 miles without any problems, but consult the owner’s manual for exact service interval. Yet, over time, the serpentine belt will fail because of the heat and friction it is subjected to every day, and have to be replaced. If you suspect your serpentine belt is failing, watch out for the following symptoms:

1. Squealing noise from the front of the vehicle

If you notice a squealing noise coming from the front of your vehicle, it could be from the serpentine belt. This could be due to a slippage or misalignment. The only way to make the noise go away is to contact a professional mechanic and have them replace the serpentine/drive belt or diagnose the issue.

2. Power steering and AC not working

If the serpentine belt completely fails and breaks, then your car will break down. In addition, you will notice a loss of power steering, the air conditioning will not work, and the engine will no longer be able to be cooled like it should be. If the power steering fails when the vehicle is moving it could cause serious safety issues. Preventative maintenance is one way to make sure your belt does not break while you are driving.

3. Engine overheating

Since the serpentine belt helps provide power to cool the engine, a failing belt can cause your engine to overheat as the water pump will not turn. As soon as your engine starts overheating, have it inspected by a mechanic because it can lead to a breakdown and cause damage to your engine if it is left to keep overheating.

4. Cracks and wear on the belt

It is a good idea to physically inspect your serpentine belt from time to time. Check for cracks, chunks missing, abrasions, rib separation, uneven rib wear, and damaged ribs. If you notice any of these, it is time to replace your serpentine/drive belt.

As soon as you notice a squealing noise, loss of power steering, the engine overheating, or the belt looks bad, call a mechanic immediately to diagnose the problem further. YourMechanic makes getting repairs to your serpentine/drive belt easy by coming to your location to diagnose or fix issues.