Serpentine Belt vs. Timing Belt: Know The Differences

Timing belts and serpentine belts serve different purposes and are totally different in types. Serpentine belts drive the alternator, power steering pump, and AC compressor. In contrast, a timing belt synchronizes the camshaft and crankshaft’s rotation.

This is just an overview. You can find a full breakdown of the comparison by reading on.

Serpentine Belt vs. Timing Belt

Quick Comparison Between Serpentine Belt and Timing Belt

An overview of serpentine belts vs. timing belts is given below in a table:

ComparisonSerpentine BeltTiming Belt
PurposeDrives accessory pulleys Synchronizes the rotation of the camshaft and crankshaft
Consequences of failureVehicle’s electrical system will be stopped/ battery charging will be stopped. Other accessory pulleys will be out of order  The engine will stop,  damaged, misfire, and may underperform 
MaterialHigh quality reinforced rubber, fabric, flat leather, etc.Rubber, polyurethane or neoprene, fiberglass, etc.
ShapeFlat belt with ribsToothed belt
LocationIn the vicinity of accessory pulleys outside the engineUnder the timing belt cover in the engine compartment
Lifespan Around 50000- 100000 milesAround 60,000- 15,0000 miles (roughly 7 to 10 years)
Replacement CostSerpentine belt cost around $70 to $200 including the labor costTiming belt cost around $500 to $750 including the labor cost

Knowing these factors will assist you in understanding serpentine belts versus timing belts.

Comparison Between Serpentine Belt and Timing Belt

In-Depth Comparison Between Serpentine Belt and Timing Belt

We’ll discuss the differences in purpose and design in detail below. These are mainly the factors that differentiate serpentine belts from timing belts. (1)


In a vehicle’s engine, serpentine belts drive multiple components. Serpentine belts are typically used to drive alternators, air conditioning compressors, and power steering pumps.

Conversely, a timing belt synchronizes the rotations of a camshaft and crankshaft. Timing belts ensure that the valves open and close at the correct times in relation to piston movement inside the engines.

So, the purpose of the serpentine belt and the timing belt is different.

Consequences of Failure

Many components directly get power from the serpentine belt, such as the A/C compressor, power steering pump, and sometimes the water pump. So, these components will fail immediately once the serpentine belt fails. 

The other electrical components, such as the lights, horn, etc., will fail once the battery is drained, as the alternator will stop recharging the battery.

On the other hand, the timing belt failure causes engine damage, misfires, poor engine performance, and desynchronization of the camshaft and crankshaft, etc. The most important thing is that the serpentine belt will also stop working if the timing belt fails. 

This is because the timing belt aids the serpentine belt in rotating. It is evident that the serpentine belt is dependent on the timing belt.

Hence, in the event of a timing belt failure, the serpentine belt is likely to fail.


Rubber or synthetic polymer timing belts are often reinforced with fiberglass or other strengthening substances to increase their toughness and longevity. As a result of these materials, the serpentine belt is flexible enough to bend around the gears and pulleys of the engine yet robust enough to transmit the engine’s power. 

Meanwhile, timing belts are usually made of polyurethane, neoprene, or other synthetic materials, which are more flexible and less prone to wear.


Timing belts have a distinct, wide design with teeth on the inside that align with a corresponding pulley. These teeth ensure that the camshaft and crankshaft move in sync. 

Serpentine belts, on the other hand, are generally narrower and feature a smooth inner surface. They are used to operate multiple engine components at once by wrapping around various pulleys.

Nevertheless, the serpentine belt is an updated version of the V belt. However, there is still a version of the V belt in use. You may wonder why the serpentine belt is better than the V belt.

The serpentine belt is better because it’s more efficient, durable, and easier to install and maintain than a V-belt. Single & continuous loops make serpentine belts easier to route around accessory pulleys. It’s also easier to adjust and replace since it requires less tension.


The serpentine belt is usually located outside the engine compartment and connects all the accessory pulleys, such as; power steering, A/C compressor, alternator, etc.

On the other hand, the timing belt is usually located under the timing belt cover inside the engine compartment. In some cases, the timing belt can either be visible from outside the engine, depending on the type of vehicle.


Usually, the lifespan of the serpentine belt depends on the belt’s type, brand, model, and vehicle type. The approximate lifespan of the serpentine belt is around 50,000 to 100,000 miles. 

Conversely, the average lifespan of the timing belt is around  60,000 to 150,000 miles. As you can see, the timing belt is made to survive longer.  

Price Range

Replacing a serpentine belt typically costs between $70 and $200, although the price can vary depending on the make and model of your car.

As for the timing belt, replacing it usually costs around $500 to $750. 


The serpentine belt is used to drive multiple accessories in a vehicle, while the timing belt synchronizes the camshaft and crankshaft rotation in the engine.


The serpentine belt and timing belt have different purposes. However, these two belts have a strong correlation. The serpentine belt mostly depends on the timing belt for its rotation.

Usually, you cannot compare these belts since they serve different purposes.

Serpentine Belt vs timing belts Infographic


What Is The Most Important Belt In A Car?

Timing belt is the most important belt of a car. The timing belt connects the camshaft and crankshaft and synchronizes their timing. If the timing belt breaks or fails, the engine may not work anymore. This may result in further severe damage, such as engine failure and engine destruction.

Is There Any Warning Before Timing Belt Breaks?

Yes, there are various warnings before the timing belt breaks. Before the timing belt breaks, the signs are slapping, knocking, loud clicking, or failure to start the engine. Aside from these, there are other minor signs, such as misfiring, overheating, etc. 

Can You Drive A Car With A Broken Serpentine Belt?

Yes, you can drive a car with a broken serpentine belt for a short distance, but it’s not recommended as it can damage the vehicle. You may experience overheating and battery drain if you attempt to drive with a broken serpentine belt.


Well, that’s all about the serpentine belt vs. the timing belt. It is now clear that serpentine belts and timing belts are two totally different types of belts with different purposes.

However, if you are still confused about anything, you can check your car’s user manual to clarify further confusion.

Written By

Photo of author

Aaron Byrne

Hi, Aaron Byrne here. I'm an expert automotive mechanic with 10 years of experience. I work on engine parts especially timing belts for their repair, maintenance, and replacement.

Fact Checked And Mechanically Reviewed By


Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at with a passion for the automotive industry.