The serpentine belt is one of the most important parts of your car. The key question here above is what would cause a serpentine belt to shred?

Let’s look at answering that question.

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What Would Cause A Serpentine Belt To Shred?

Believe it or not, this issue happens more frequently than you might believe. In most cases, it’s caused by the tensioner pulley being slightly misaligned.

When you replace the serpentine belt, it’s important to align the pulley with the right tools; such as a serpentine belt removal tool and pulley alignment wrench.

What Causes A Serpentine Belt To Rip?

Serpentine belts are used on a variety of different engines, and they’re also used in different positions on the same engine. But they all do the same thing: Drive various components that aren’t connected to the crankshaft.

There are two critical factors that will determine how long a serpentine belt lasts. These are:

Abrasion. The belt is usually driven by a pulley that has one or more grooves cut around its outside surface. The friction from being driven through these grooves will gradually wear away at the belt, eventually causing it to fail.

Temperature. A serpentine belt is made of rubber, and rubber is a very temperature-sensitive material. As the engine warms up, it will expand slightly. If the belt isn’t made long enough to accommodate this expansion, it can become so tight that it snaps under its own tension.

This is particularly true if the drive pulley is in front of an air conditioner compressor or some other high-temperature accessory.

This can be a particular problem in vehicles with short water pumps or alternators located close to the front of the engine block because they’re being driven by a relatively long serpentine belt with little room to stretch as things heat up.

Can You Drive With A Shredded Serpentine Belt?

Basically, you should be able to drive it to a safe space where it can be towed or repaired. If the belt is snapped and dangling in the engine compartment, remove it before moving the vehicle to prevent further damage.

The serpentine belt drives all of the accessories on your engine that are powered by the front of the crankshaft. On an interference engine, if that belt snaps while you’re driving, pistons will collide with valves and this will cause major internal damage. If your car has a timing chain instead of a timing belt, you should be fine if your serpentine belt snaps.

If any of these components have been damaged by a snapped serpentine belt, they’ll likely need to be replaced. The power steering pump may also need to be replaced if there’s a leak or it was damaged by the tensioner or pulley when the belt broke.

Is It Common For A Serpentine Belt To Break?

The serpentine belt may not be prone to breaking, but it does wear out over time. When a serpentine belt wears – or if the belt becomes damaged or contaminated – the engine accessories may not be able to spin at the proper speed.

The result can be poor fuel economy, poor acceleration and/or decreased power steering assist. In some cases, a worn or damaged serpentine belt will cause a high-pitched squealing noise that is sometimes mistaken for a problem with an accessory such as the alternator or air conditioner compressor. A damaged or worn belt can also cause the engine to overheat if it drives the water pump, which cools the engine.

If your serpentine belt is damaged or extremely worn, it should be replaced immediately by an ASE-certified technician. This is especially true if you drive in extreme weather conditions; your car’s cooling system and other accessories need to work properly to keep you safe on the road.

Your mechanic will also check that all of your belts are in good condition and replace them as needed during your regular maintenance visit.

While you’re there, make sure your mechanic performs a full vehicle inspection to ensure that everything under the hood is running smoothly and that no other issues require attention.

What Happens When Your Serpentine Belt Comes Off?

When the serpentine belt fails, your car will start to lose all of its power accessories. The air conditioner, power steering and alternator will no longer work. You’ll also likely notice a rattling sound coming from under your hood.

Troubleshooting the problem can be difficult if you don’t know what’s causing it. Start by quickly checking the belts themselves for cracks or fraying, which is a sign that they need to be replaced.

Once you’ve replaced the belts and made sure they’re in place properly, you can test each individual component to see which one failed.

The serpentine belt powers different components in your engine, so a number of things can go wrong when it’s not working properly. The best way to figure out what exactly is going on is by starting your car and listening for noises that indicate an issue with a specific component.

If you hear a rattling sound coming from the front of the engine, that usually indicates that the alternator has stopped working. If there’s a burning smell coming from under the hood but you can’t find its source, chances are your serpentine belt has broken off from the engine block and is probably sitting somewhere on top of your engine or under one of your hoses.

Can Serpentine Belt Cause Rough Idle?

If your car is idling roughly and you can’t figure out what the problem is, a bad serpentine belt could be to blame. The serpentine belt is located under the hood, where it winds around multiple pulleys connected to various engine accessories.

The serpentine belt is responsible for turning the pulleys as the engine runs. When the serpentine belt fails or has an issue, the rough idle you experience is usually caused by a pulley that isn’t turning correctly.

A bad serpentine belt will make your engine idle roughly because it won’t be able to power certain accessories that are necessary for smooth idling.

How Long Should A Serpentine Belt Last?

Serpentine belts are built to last—much longer than before because of advancements in rubber technology. Under ideal conditions, a belt should stick with you for an average of 60,000 to 100,000 miles.

But there are many factors that can affect how long your serpentine belt will last—from vehicle age and make to engine care and storage practices.

Today’s serpentine belts use much better rubber compounds and they’re built to tighter manufacturing tolerances than in years past.

They’re also nearly impervious to heat, which means they resist drying out, cracking and breaking down as easily as belts made decades ago. That’s why you’ll see a lot of belts still going strong after 60K miles or more.

What Happens If Belt Breaks While Driving?

If your car has a timing belt, replace it according to the manufacturer’s recommendation — generally every 50,000 to 70,000 miles.

If your car has a timing chain and you hear a rattling noise, get it checked out as soon as possible. If the timing belt or chain breaks while driving, this can cause major engine damage.

When the timing belt breaks, the crankshaft will continue to spin at 1000 rotations per minute, while the camshaft will stop turning. As a result, the pistons will continue to rise and fall in their cylinders, but they will strike closed valves. This will bend or break them — and possibly shear off other parts of the engine as well.

When valves are bent or broken, they end up in your engine’s cylinders. The pistons will strike them with enough force to blow holes through your engine block or cylinder head.

This is commonly referred to as “throwing a rod,” because it means that your connecting rods have been thrown from their bearings under so much pressure that there is nothing left of them but twisted pieces of metal.