Belt

Your vehicle’s engine has the critical job of transmitting power to several major car parts; the air conditioning compressor, alternator, power steering pump, and water pump. But how do all these systems and components function simultaneously? Using rotational energy from the engine's crankshaft, it’s the drive belts that help to turn and provide power to these parts, and are therefore crucial to the function of both your vehicle’s auxiliary and electrical systems.

Engine belts essentially act as the connection between each component and system to the pulleys being powered by the engine’s crankshaft. In the case of newer vehicles, these are held in place by a tensioner, while older vehicles require tension to be set. Without properly functioning engine belts, the AC won’t work, the alternator won’t charge the battery, the power steering pump can’t assist with steering, and the water pump won’t cool the engine.

How Many Belts Does a Car Have?

It depends. Most modern cars just have one, a serpentine belt. This one winds around multiple pulleys throughout the engine compartment, requiring a single belt to provide power to your engine’s components and systems. Older vehicles have multiple V belts to turn each of the pulleys on the various components separately.

These other common V belts include:
- Alternator Belts: These are by far the most common, as any vehicle with an alternator needs one
- Power Steering Belts: These drive the power steering pump to provide energy to the system and make steering easier
- Water Pump Belts: These provide power to the cooling system so your engine will not overheat. Sometimes the water pump is driven by the timing belt or chain instead
- AC Compressor Belts: These turn AC compressors so you can keep your cabin cool

If you don't have a classic or just plain very old car, you've probably got a serpentine belt under the hood, which combines the functionality of all of these types of V-belts by wrapping, like a serpent, around the pulleys for each of these components.

Replacement Protocol for Engine Belts

While a drive belt can last between 50,000 and 100,000 miles, the only true way to know when one needs replacement is by visual inspection and in some cases, what it’s sounding like. Most are made from durable rubber compounds, but rubber warps over time and it’s important to make the replacement before you get stuck on the side of the road.

Visual signs of wear like abrasions, cracks, and damaged ribs are sure indicators that your belt is on its way out. When driving, this kind of damage can cause squealing noise from the front of the vehicle, or even engine overheating. If you’re experiencing any of these symptoms of a worn engine belt, your best bet is to replace it as soon as possible to avoid any safety issues while driving. In the event of belt failure, it’s recommended to pull over and stop driving the vehicle immediately, as further use could cause serious damage to your engine.

With any belt replacement job, the first step is determining which system your vehicle uses - one or multiple belts, and by simply looking at the engine compartment under the hood, you’ll likely be able to tell which one you’re working with. If you’re seeing one longer belt attached to multiple pulley systems, be sure to grab a serpentine belt tool and use our DIY guide on how to replace a serpentine belt.

Finding the Right Belt For Your Vehicle

Simply set the year make and model of your vehicle above and shop engine belts specifically designed for a custom fit. Making sure you have working drive belts is a crucial part of vehicle maintenance, and it’s an easy job for any DIYer. You can find all the parts and tools you need like belt tensioner component kits that come complete with everything you need to do the job right.

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