The timing belt synchronizes the opening and closing of the engine valves with the pistons. Contrarily, the driving belt powers the other engine accessories like AC, power steering, and alternator. The timing belt has inner teeth and it connects the camshaft with the crankshaft. In contrast, the driving belt has V shape grooves and operates to multiple related accessories.
The driving belt vs timing belt has many other differences as well. To know them in detail, keep reading this article.
Driving Belt Vs. Timing Belt: Quick Differences
A driving belt (also known as a serpentine belt) and a timing belt are completely different in case of function and connectivity. Here’s a quick difference between driving belt and timing belt.
| Features | Timing Belt | Driving Belt |
| Function | Synchronizes the crankshaft and camshaft. Drives the water pump. (in some cars) | Provides power to the car accessories like AC compressor, alternator, and power steering. |
| Appearance | Has inner teeth | Has V shape inner grooves |
| Material | Stiff rubber, neoprene, or polyurethane | Neoprene or EPDM |
| Connectivity | Crankshaft sprocket, camshaft(s) sprocket, and the water pump pulley | Crankshaft sprocket, AC sprocket, alternator pulley, and water pump pulley |
| Location | Protected under the timing cover | Outside the engine usually without any cover |
| Lifespan | 60,000 to 100,000 miles on average | 50,000 to 100,000 miles on average |
| Failure consequences | Engine misfiring, rough idling, difficulty starting, engine overheating, unusual noises coming from the engine. | the car’s AC, power steering, and alternator will face problems operating, the engine will overheat. |
| Replacement Difficulty | Difficult to replace. May take 4 to 8 hours. | Easy to replace. May take 15 minutes to 1 hour. |
| Replacement Cost | Parts: $100 to $400Labor: $400 to $600 | Parts: $15 to $80Labor: $75 to $120 |
Driving Belt Vs. Timing Belt: In-Depth Differences
Although due to their names, timing belts and drive belts may seem the same, they have significant differences. Let’s discuss the difference between timing belt and drive belt in detail.
Function
Timing belt synchronizes the rotation of the crankshaft and the camshaft in a car engine to ensure efficient combustion.
In some cars, the water pump is also attached to the timing belt with the help of a pulley. So, another function of the timing belt is driving the water pump to efficiently circulate the coolant and keep the engine from overheating.
On the other hand, the driving belt receives power from the crankshaft rotation. It passes that power to the car’s accessories including air conditioning, alternator, and power steering.
Summary:
The timing belt helps the camshaft and crankshaft to rotate in sync, while the drive belt drives the other engine accessories.
Appearance
The timing belts have inner teeth and modern timing belts have curvilinear-shaped teeth. These teeth are designed to grip the crankshaft and camshaft pulleys firmly. Timing belt teeth can break due to various reasons like incorrect tension and misalignment.
Whereas, a driving belt has molded V-shaped grooves into its inner surface. Unlike the timing belt, the grooves of the driving belt usually don’t break, but they will get cracked or worn out over time.
Summary:
The timing belt has teeth to connect with the pulleys. On the other hand, the driving belt has grooves molded on the belt surface.
Material
The older drive belt was made with neoprene. Nowadays, these belts are made with high-quality Ethylene Propylene Diene Monomer (EPDM) rubber.
In contrast, timing belts are made of stiff rubber, neoprene, or polyurethane. The rubber used in the timing belt is reinforced with corded fibers for ensuring durability.
Connectivity
A timing belt is a relatively smaller belt that connects fewer things than the drive belt. For example:
- Crankshaft
- Camshaft
- Water pump (in some cars)
- Injector pump (in some cars)
- Oil pump (in some cars).
On the other hand, the driving belt is a long belt connecting multiple accessories together. For example
- Crankshaft
- AC compressor
- Power steering pump
- Alternator
- Auxiliary air pump (in some cars)
- Water pump (in some cars)
- Works as a fan belt (in some cars)
Summary:
The timing belt is connected to the camshaft, crankshaft, and water pump. Alternatively, the driving belt is connected to the crankshaft, AC compressor, alternator, and other car accessories.
Location
A driving belt is usually located outside the engine without any cover, and it is easily accessible. You will notice the drive belt whenever you open the car’s hood.
On the other hand, a timing belt is protected under the timing cover and you can’t see it right away. Compared to the driving belt, it is harder to access a timing belt location in cars.
You may need to remove a number of components to get to the timing belt. For example, the serpentine belt, outer crankshaft pulley, and timing cover.
Lifespan
Depending on the engine, driving habit, and car model, a timing belt can last around 60,000 miles to 100,000 miles(2).
On the other hand, older neoprene drive belts usually used to last for 50,000 miles. And modern EPDM (Ethylene Propylene Diene Monomer) drive belts last around 100,000 miles.
Failure Consequences
When a timing belt fails, your car will suffer engine misfiring, rough idling, and difficulty starting. Moreover, if a timing belt is completely broken, it can severely damage an interference engine by leading the pistons and valves to collide.
Finally, the driving belt itself is indirectly dependent on the timing belt. The timing belt ensures that the engine runs efficiently. And, the driving belt is run by the engine’s crankshaft pulley. So, if the timing belt fails, the engine will also fail. Eventually, this will lead to the stopping of driving belts.
On the other hand, when a driving belt fails, the alternator won’t supply power to the battery. As a result, your car’s lights, radio, and other battery-generated accessories will stop working.
Moreover, the steering will be difficult to turn and the engine will get overheated as the coolant won’t flow. your car’s AC won’t work.
Both belt failures will lead to some common problems including car stalling, engine light on, engine overheating, and unusual squeaking or ticking noises.
Replacement Difficulty
Since the driving belt is easily accessible and really easy to replace. Depending on expertise, a drive belt can be replaced within 15 minutes to an hour and it doesn’t require many tools.
On the contrary, the timing belt is difficult and time-consuming to replace. You need to dissemble many components like the serpentine belts, outer crankshaft pulley, timing cover., etc. Timing belt replacement can take 4 to 8 hours depending on the expertise level, car model, and engine type. And it requires a lot of specialized tools.
Summary:
The timing belt is more difficult to replace than the Driving belt.
Cost
Changing a drive belt is way cheaper than changing a timing belt. A drive belt can cost around $15 to $80. And for the labor cost, you need to spend around $75 to $120. So, within $100 to $200, you can cover the drive belt replacement cost.
In contrast, a timing belt can cost you $100 to $400. And the labor cost for replacing a timing belt is around $400 to $600 since it’s complicated to replace. In total, a timing belt replacement cost can be around $500 to $1000 on average.
Summary:
The timing belt is more costly to replace than the driving belt.
These are the main differences between a timing belt and drive belt.
FAQs
What Are The 3 Belts In A Car?
Three belts in a car are the timing belt, drive belt, and V belt. A timing belt synchronizes the camshaft and crankshaft rotation. The drive belt or serpentine belt drives the accessories like AC, alternator, and water pump. V-belts were used in older model cars instead of serpentine belts.
Why Is A Serpentine Belt Called That?
As it is connected to multiple pulleys in a snake-like curved manner, it is called the serpentine belt. The belt is also called an accessories belt and drive belt.
Do Belts Need Lubrication?
No, the belts don’t need any lubrication. The pulley bearings connected to the belts require lubrication. But engine oil provides enough lubrication to them. So, they also don’t need external lubrication.
Conclusion
That’s all about Driving Belt Vs Timing Belt. Both belts are really important for your car. So, you need to ensure proper maintenance of them. And replace both belts after every interval recommended by the manufacturers.
Now it’s time for me to go. Have a great day!
