How Much Does A Serpentine Belt Replacement Cost? (2024)

The accessory drive belts are vital for the operation of the vehicle's accessory systems, such as the air conditioning and power steering. The accessory belt, also known as the serpentine belt, can also drive the water pump, a major cooling system component, and the alternator, the component responsible for charging the battery and maintaining the vehicle electronics. A loose, worn, or missing belt can result in several system failures. In this article, we’ll look at the cost of a serpentine belt replacement, along with the signs and symptoms of a belt on its way out.

What Is A Serpentine Belt?

A serpentine belt is a single rubber belt that is driven by the crankshaft to drive multiple pulleys or accessories. Before having one singular serpentine belt, vehicles had multiple ‘V-belts’. Manufacturers transitioned to the single serpentine belt to make engines more efficient, easier to maintain, and cheaper to manufacture. The following are the accessories commonly powered by the serpentine belt:

• Alternator
• Water pump
• Power steering pump
• A/C compressor
• Cooling fan
• Air pump

Worn Serpentine Belt Symptoms

The following is a list of possible symptoms experienced with a worn or loose serpentine belt:

• Belt squealing on screeching
• Charging indicator light on
• Overheating
• Loss of power steering
• Inoperable air conditioning
• Dim lights
• Check engine light illuminated

How To Inspect A Serpentine Belt

Serpentine belts should be visually inspected for cracks, tears, and proper tension. Most serpentine belts use automatic belt tensioners. However, some still use manual tensioners. As the belt wears, it will stretch and crack, becoming loose. A loose belt will slip on the pulleys and fail to effectively drive them. If a belt is cracked, torn, or excessively loose, the belt needs to be replaced.

Visual Inspection

Fluids such as oil, coolant, and/or power steering fluid leaking onto the belt will eventually degrade the belt's rubber, making it soft. A saturated belt is more prone to stretches, cracks, and tears. If there are any physical imperfections in a belt, it should be replaced. After visually inspecting the belt, the tension should be checked.

Belt Tension

You can use a belt tension gauge to check for proper tension. However, in most scenarios, you do not have to. A belt should only be able to turn approximately 90 degrees at the loosest point. A belt can have a faulty automatic tensioner, a misadjusted manual tensioner, or be worn. If the belt cannot be adjusted to the proper tension specification with a manual tensioner, the belt must be replaced. If the belt is found to be too loose with a properly functioning automatic tensioner, the belt should be replaced.

Belt Inspection Tool

The use of a belt inspection tool is an effective way to inspect a belt. These tools are occasionally offered at parts stores and via online promos for free.

When To Replace A Serpentine Belt

You should replace the serpentine belt any time it fails an inspection. It’s uncommon for manufacturers to indicate when to replace a serpentine belt in the service tables. Commonly, the serpentine belt would be inspected with every oil change or mileage interval service. However, if there are repairs being performed that require the removal of the serpentine belt, you should replace the belt at that time.

How To Replace A Serpentine Belt

Serpentine belts will typically only require basic hand tools to remove. Some belts are easier to remove with the use of a serpentine belt tool kit. Oftentimes, these can be picked up from your local parts store for around $50.

On most domestic vehicles, the belt routing diagram can be found on the hood or on the upper radiator support. On imported vehicles, it’s likely the diagram is not on the vehicle and will have to be found in the service manual. If you do not have a service manual, pay close attention to the belt's routing before removing the belt.

The steps involved in replacing a serpentine belt are:

1. Locate the belt tensioner.
2. Place the socket or belt tensioner tool on the tension bolt.
3. Press or pull the tensioner in the correct direction to loosen the belt.
4. Remove the belt.
5. Install the new belt using the correct routing.
6. Remove tension to position the belt over all the pulleys.

Belt Replacement Tips

1. Always verify the correct belt routing.
2. Position the belt on the ‘smallest’ pulley last.
3. Remove the front wheel that allows access to the belt, when possible. This allows you to ensure the belt routing and positioning on the crankshaft pulley. (this only applies to transversely-mounted engines)
4. Fix fluid leaks.
5. Some belts are 'stretch to fit' and they do not have a tensioner. Once they become loose, they require replacement.

How Much Does it Cost To Replace A Serpentine Belt?

The replacement cost for a drive belt or serpentine belt is typically not too expensive. RepairPal estimates a serpentine belt replacement will cost between $110 and $150. A drive belt or serpentine belt replacement can go down to around $50 if you do the repair yourself. We also found the following estimates for a complete serpentine belt replacement (including labor) for various popular models, including the Ford F-150:

The serpentine belt is a simple yet important component of the vehicle as it affects multiple systems. If you suspect your serpentine belt is worn, or you are experiencing any of the symptoms above, inspect your belt. A simple belt replacement can save you in the long run by avoiding a dead battery, an overheating engine, or a loss of power steering.