Serpentine Belt: Symptoms, Replacement Cost, and More

In the past, automobile engines had multiple V-belts (also known as fan belts)—but that’s no longer the case. Nearly all vehicles now have a single serpentine belt at the front of the engine. The design is more efficient and easier to replace than several V-belts.

Of course, like any other rubber component, your car’s serpentine belt can eventually wear out. When that happens, you’ll want to replace the belt right away to avoid a breakdown and additional repairs.

How Much Does it Cost to Replace a Serpentine Belt?

You might be wondering: Is replacing a serpentine belt expensive?

The answer is usually no. In comparison to most other automotive repairs, replacing a serpentine belt is generally fairly affordable.

If you choose to have a professional replace your car’s serpentine belt, you can usually expect to pay somewhere between $150 and $250 to get the job done. Of course, the serpentine belt replacement cost will depend on various factors, such as the year, make, and model of your vehicle.

You can save money by replacing the serpentine belt yourself if you have the tools and the know-how. CarParts.com has a wide variety of replacement serpentine belts available for various makes and models.

Watch these videos to understand how to replace your serpentine belt:

What Does a Serpentine Belt Do?

A serpentine belt is a single belt that wraps around multiple engine-driven accessories fitted with pulleys. The serpentine belt also loops around the engine’s crankshaft pulley. An automatic tensioner keeps the belt in position.

Whenever the vehicle is running, the engine’s crankshaft pulley turns the serpentine belt. The belt then drives the various accessories (i.e., alternator, air conditioning compressor, etc.) via their individual pulleys. The accessories operate whenever they’re rotating.

Most older serpentine belts are made of neoprene rubber, whereas many newer belts are made from a tougher, ethylene propylene diene monomer (EPDM) synthetic rubber.

Bad Serpentine Belt Symptoms

Although modern serpentine belts are generally quite robust, they can eventually wear out or break. When that happens, you’ll likely notice one or more of the following symptoms:

Abnormal Serpentine Belt Noise

In many cases, the first sign of a bad serpentine belt is a squealing noise (caused by a glazed surface). Keep in mind, however, that a weak belt tensioner or misaligned accessory pulley can cause the same sound.

Visible Belt Wear or Damage

Serpentine belts (especially those made of neoprene rubber) tend to develop cracks on their grooved side. Other signs of belt damage include a glazed surface, frayed edges, and missing chunks. Serpentine belts can also suffer from contamination due to fluid leaks (e.g., oil and coolant).

If your serpentine belt shows signs of wear, damage, or contamination, you’ll want to replace it immediately to avoid any subsequent problems.

Belt-driven Accessories Stop Working

If you choose to ignore a worn or damaged serpentine belt, there’s a good chance the belt will eventually break.

When that happens, all of the belt-driven accessories at the front of the engine—including the alternator, air conditioning compressor, and power steering pump (if equipped)—will cease to operate. The water pump, which is driven by the serpentine belt on nearly all modern vehicles, will also stop working.

As a result, you’ll notice the charging system warning light (and possibly some other warnings) immediately illuminate on the dashboard. Your car’s air conditioner will no longer work, and the steering wheel will be extremely difficult to turn (if your car has hydraulic power steering).

What’s worse, if the serpentine belt drives the water pump, your car’s engine will begin to overheat, potentially leading to catastrophic damage.

Note: On some vehicles, the brake booster relies on pressurized power steering fluid to provide braking assist. A broken serpentine belt can prevent the power steering pump from operating, thereby resulting in a loss of braking assist.

When To Replace a Serpentine Belt?

You should replace your serpentine belt as soon as it starts showing symptoms. Luckily, serpentine belt symptoms are quite apparent and easy to spot. However, serpentine belt replacement is also part of most vehicles’ maintenance calendars. Most vehicle manufacturers recommend replacing the serpentine belt every 50,000 miles to 100,000 as preventative maintenance. Curious about your serpentine belt’s replacement interval? Check your vehicle’s owner’s manual.

The serpentine belt is a component that must be replaced before it even has a chance to fail. The belt is a critical component that powers key vehicle functions such as the power steering, air conditioning, and alternator. If this component fails, your vehicle is going to have major drivability issues that can pose risks to your safety.

How Long Does a Serpentine Belt Last?

In the past, many professionals recommended replacing a serpentine belt every four to seven years or 50,000 to 60,000 miles. Today’s EPDM belts are more robust, though, and often last well over 100,000 miles.

It’s a good idea to keep an eye on your car’s serpentine belt. You’ll want to replace the belt immediately whenever its integrity is in question.

Installing a new belt is usually a relatively straightforward and affordable affair—and it’s cheap insurance against a potentially costly breakdown.

Can You Drive Without a Serpentine Belt?

You cannot continue to drive without a serpentine belt. Without the belt, the alternator will no longer charge the battery, and your vehicle will eventually stop running. You’ll also lose steering assist (if your car has hydraulic power steering), making the vehicle unsafe.

Finally, if your car has a serpentine belt-driven water pump, the engine will begin to overheat, possibly resulting in major internal damage.