What is a Serpentine Belt?

While many items are on a vehicle’s maintenance schedule, some are lesser-known than others for many drivers. 

Some components require maintenance often, like oil flushes and filter replacements. Other parts are capable of carrying on for many miles, even years, before needing attention. The serpentine belt is a member of the latter group. Below, we will explain what it is, how it works, and when to expect it to need service.

What is a serpentine belt?

Vehicles tend to have multiple belts that you’ve probably heard of in the past. You might have even listened to the serpentine referred to as an accessory or a fan belt

Not to be confused with a timing belt, this is a long rubber belt in charge of transporting power to the engine accessories; the serpentine belt holds a crucial position within most vehicles. It sits within the grooves of certain parts, allowing it to wrap around them and multiple pulleys like a snake. Hence ‘serpentine.’ 

As it rotates within a moving engine, it carries power to certain parts, causing them to spin. The belt itself is pretty apparent, even to a novice! It’s a long, continuous piece that wraps around the power steering pump, alternator, air conditioning compressor, and, depending on the make and model of the vehicle, the water pump.

The serpentine belt is so crucial to the engine that when it breaks, everything stops working.  

What are the warning signs of a bad serpentine belt?

While engineered to last many miles, the serpentine belt is most certainly not free of wear. As you can imagine, the engine and its parts are subject to a lot of friction and heat as it pulls various parts. Some will last longer than others, but they all exhibit similar symptoms of wear. Keep an eye and ear out for the signs that warn of a serpentine belt on its way out:

  • Check Engine Light Engages in the Dashboard
  • Visual Signs of Wear on the Belt
  • Loss of Performace in the Power Steering or Stalling
  • Steady yet Unusual Sounds from the Engine

How long do serpentine belts last?

Depending on its condition, the belt can last many miles. If it sustains its duties well, our vehicle maintenance schedule suggests replacing the belt at 100k miles. For some, it might require replacing around the 60k miles mark.

Serpentine Belt Replacement & Repair at Casey’s Automotive in Chantilly, Virginia

If your car or truck is exhibiting any of the issues listed above, with its power steering system, sudden engine stalls, or the battery drains for no seemingly apparent reason, bring it into Casey’s for an inspection immediately. Replacing a belt before it breaks can significantly affect how much is left in your wallet after service!


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